CN116705580A

CN116705580A - Vacuum isolation importer and electron microscope

Info

Publication number: CN116705580A
Application number: CN202210187136.2A
Authority: CN
Inventors: 于陈陈
Original assignee: Suzhou Sishi Technology Co ltd
Current assignee: Suzhou Sishi Technology Co ltd
Priority date: 2022-02-28
Filing date: 2022-02-28
Publication date: 2023-09-05

Abstract

The invention relates to a vacuum isolation importer and an electron microscope, wherein the electron microscope comprises a valve and a vacuum isolation importer, the valve is arranged at one end of the vacuum isolation importer, and the vacuum isolation importer can drive the valve to reciprocate so as to open or close the communication state between an ultrahigh vacuum cavity and other cavities, thereby meeting the requirements of the electron microscope such as use, maintenance, abnormal protection and the like, and improving the use efficiency. The vacuum isolation importer comprises a motion execution cavity, a motion guide rod and an elastic element, wherein the motion execution cavity is arranged on one side of the flange plate, one end of the motion guide rod and the elastic element are accommodated in the motion execution cavity, so that the pressing and the height of the elastic element can not influence the length of the vacuum isolation importer, the inner length of the motion execution cavity can be equal to the motion stroke, the design of the vacuum isolation importer can be minimized, the interference between the vacuum isolation importer and other parts in the electron microscope is avoided, and the assembly and the debugging of equipment are also facilitated.

Description

Vacuum isolation importer and electron microscope

Technical Field

The invention relates to the technical field of electron microscopic imaging, in particular to a vacuum isolation importer and an electron microscope.

Background

An electron microscope comprises a Scanning Electron Microscope (SEM) and a Transmission Electron Microscope (TEM), and is characterized in that an electron beam emitted by an electron gun passes through a condenser lens and an objective lens along the optical axis of a lens body in a vacuum channel to be focused into a light spot to be irradiated on a sample, and secondary electrons or back Scattered Electrons (SEM) generated by the interaction of the electron beam and the surface of the sample, orAnd collecting information (TEM) of scattered electrons interacted with the structure in the process of penetrating the sample, and obtaining the microscopic morphology or composition structure of the sample surface. The vacuum degree is required to be as high as possible in all areas where electrons run; otherwise, the normal operation of the electron microscope is affected or the lifetime of the electron source is reduced. If the vacuum degree is not high, the high-speed electrons meet and interact with gas molecules to cause random scattering of the electrons, so that 'glare' is caused and the contrast of an image is weakened; ionization and discharge of the electron gun also occur, resulting in unstable electron beams and flickering; residual gas can corrode the incandescent filament, so that the service life of the filament is shortened; residual gas can severely contaminate the sample, affecting the capture of images. Therefore, the electron source part of the electron microscope and the working area of the sample stage are always kept in a high vacuum state. Modern high resolution electron microscopes typically employ thermal or cold field emission electron sources which impose more stringent requirements on local ambient vacuum levels, at least greater than 1x10 ^-9 Torr, has entered the ultra-high vacuum range, which requires the electron source to operate in a higher vacuum environment than the sample stage, to achieve and maintain the ultra-high vacuum therein. The design aspect of the vacuum system must adopt a vacuum pump (usually an ion pump and a suction pump) with higher end, adopts a multi-cavity cascade design, and gradually increases the high vacuum of the sample area to the ultrahigh vacuum required by the electron source area; in addition, in terms of the process, the materials of the cavity and the materials of the built-in parts are strictly screened, and the ultra-high vacuum can be realized by long-time high-temperature baking and exhausting. Even without regard to material costs, time costs and risk monitoring of equipment are an important part of design considerations. The introduction of an electron gun valve is based on this consideration. Once the vacuum of the system or the working condition of the electron gun is abnormal, or the system needs to be maintained, the vacuum area of the sample table needs to be exposed to the atmosphere, and the like, the valve of the electron gun can be closed, and the ultrahigh vacuum cavity where the electron gun is positioned is kept isolated from the external space. Once the device is restored, it can be quickly put into operation.

The electron gun region and the sample stage region of the electron microscope need to be maintained in different vacuum states, and valves are usually introduced to isolate the vacuum in order to enable independent control between them to meet service and test requirements or to improve time efficiency. The motion device for driving the valve is generally a vacuum isolation importer adopting a linear mechanical motion mode. In order to facilitate transportation and ensure safety, the electron source or ion source vacuum isolation importer is generally required to be in a pre-loading mode through an elastic element, so that the valve closes the vacuum cavity in a natural state, thereby achieving the purpose of vacuum isolation. In the existing design of the vacuum isolation importer, the elastic element is usually installed in the cavity of the motion actuator of the vacuum isolation importer, the length of the preloaded state of the elastic element determines the length of the cavity of the motion actuator, which leads to the length of the cavity of the motion actuator, not only meeting the motion stroke, but also being capable of accommodating the pressure and height of the spring, so that the design of the traditional vacuum isolation importer cannot be miniaturized. Because the transmission electron microscope is a precise instrument, the peripheral components are numerous, and the miniaturization design of the vacuum isolation importer can not be realized, so that the vacuum isolation importer is easy to interfere with other parts when being arranged in the electron microscope, and the disassembly is difficult when being assembled and maintained.

Disclosure of Invention

In view of the above, it is necessary to provide a vacuum isolation introducer capable of achieving a compact design and an electron microscope including the vacuum isolation introducer, which are designed to prevent interference with other parts when the vacuum isolation introducer is mounted in the electron microscope by the compact design of the vacuum isolation introducer, thereby further achieving the compact design of the electron microscope.

According to one aspect of the present application, there is provided a vacuum isolation introducer comprising:

a flange plate;

the motion execution cavity is fixedly arranged on one side of the flange plate;

one end of the motion guide rod penetrates through the motion execution cavity, the other end of the motion guide rod penetrates through the flange plate, the other end of the motion guide rod is positioned on one side, away from the motion execution cavity, of the flange plate, and the motion guide rod can reciprocate along the axis direction of the motion guide rod relative to the flange plate under the action of external force; a kind of electronic device with high-pressure air-conditioning system

And one end of the elastic element is connected with the flange plate, the other end of the elastic element is connected with one end of the motion guide rod far away from the motion execution cavity, and the elastic element can provide a preloading force for enabling the motion guide rod to have a motion trend pointing to the flange plate from the motion execution cavity.

According to the vacuum isolation importer, the motion execution cavity, the motion guide rod and the elastic element are arranged in the vacuum isolation importer, so that the motion execution cavity is arranged on one side of the flange plate, one end of the motion guide rod is contained in the motion execution cavity, the other end of the motion guide rod penetrates through the flange plate and is positioned on the other side of the flange plate, the elastic element is arranged on one side of the flange plate far away from the motion execution cavity, meanwhile, one end of the elastic element is connected with the flange plate, and the other end of the elastic element is connected with the motion guide rod, so that the elastic element is arranged outside the motion execution cavity, the pressing height of the elastic element cannot become one of factors affecting the length of the importer, and the inner length of the motion execution cavity can be equal to the motion travel, so that the design of minimizing the vacuum isolation importer can be realized, and interference between the vacuum isolation importer and other parts can be avoided when the vacuum isolation importer is arranged in an electron microscope.

In one embodiment, the elastic element can be in a preloaded state under the action of the preload force or in a compressed state under an external force;

when the elastic element is in the pre-loading state, the dimension of the elastic element along the axial direction of the motion guide rod is the maximum; when the elastic element is in the compressed state, the elastic element can be deformed in a recoverable manner so as to minimize the dimension of the elastic element along the axial direction of the motion guide rod.

In one embodiment, the vacuum isolation introducer further comprises a diaphragm bellows, one end of the diaphragm bellows is fixedly connected to the flange plate, the other end of the diaphragm bellows is fixedly connected to the movement guide rod, and the elastic element and the movement guide rod are partially accommodated in the diaphragm bellows.

In one embodiment, the diaphragm bellows is capable of being deformed in a restorable manner along the axial direction of the motion guide rod, and the dimension of the elastic element along the axial direction of the motion guide rod is larger than the dimension of the diaphragm bellows along the axial direction of the motion guide rod.

In one embodiment, one end of the motion guide rod accommodated in the motion executing cavity and part of the inner wall of the motion executing cavity jointly define a closed cavity.

In one embodiment, the motion executing cavity is provided with a gas feeding hole for introducing high-pressure gas, and the gas feeding hole is communicated with the external environment and one end of the motion guide rod accommodated in the motion executing cavity;

the high pressure gas can move in the direction of the axis of the motion guide rod through the gas feed Kong Qudong to reduce the volume of the closed cavity and can place the motion guide rod in the compressed state.

In one embodiment, the vacuum isolation introducer comprises a drive assembly at least partially housed within the motion-performing cavity, the drive assembly configured to drive the motion guide rod to move in a direction of its own axis so as to place the resilient element in the compressed state.

In one embodiment, the driving element comprises an excitation power supply and a solenoid coil, the excitation power supply is electrically connected to the solenoid coil, the solenoid coil is accommodated in the motion execution cavity and sleeved on a part of the motion guide rod, and the power supply is used for generating excitation current so that the solenoid coil generates a magnetic field for driving the motion guide rod to move.

In one embodiment, the motion guide rod includes a magnetic conduction portion, where the magnetic conduction portion is at least partially exposed in the motion execution cavity and is located on a side, away from the motion execution cavity, of the flange plate, the magnetic conduction portion and the motion execution cavity are made of soft magnetic materials, and the magnetic field generated by the solenoid coil can drive the magnetic conduction portion to move along an axial direction of the motion guide rod in a direction close to the motion execution cavity, so that the elastic element is in the compressed state.

According to another aspect of the present application there is provided an electron microscope comprising a valve and a vacuum isolation introducer as described above, the valve being mounted at one end of the vacuum isolation introducer; the electron microscope is also provided with an ultrahigh vacuum cavity, and the vacuum isolation importer can drive the valve to reciprocate along the axial direction of the vacuum isolation importer so as to open or close the ultrahigh vacuum cavity.

According to the electron microscope, the valve and the vacuum isolation importer are arranged in the electron microscope, so that the valve is connected with the vacuum isolation importer, and the valve is pushed by the vacuum isolation importer to perform linear and linear reciprocating motion so as to open or close the ultrahigh vacuum cavity, and the ultrahigh vacuum cavity can be opened to normally work when the electron microscope normally works; the vacuum state of the ultrahigh vacuum cavity can be strictly protected by closing the electron microscope in a transportation and carrying state and a maintenance state.

Drawings

In order to more clearly illustrate the embodiments of the application or the technical solutions in the prior art, the drawings that are required for the description of the embodiments or the prior art will be briefly described, it being obvious that the drawings in the following description are only one embodiment of the application, and that other embodiments of the drawings can be obtained according to these drawings without inventive effort for a person skilled in the art.

FIG. 1 is a schematic illustration of an application of the vacuum isolation importer provided by the invention in an electron microscope;

FIG. 2 is a front view of a vacuum isolation introducer of a first embodiment provided by the present invention;

FIG. 3 is a schematic perspective view of a vacuum isolation introducer according to a first embodiment of the present invention;

FIG. 4 is a front view of a vacuum isolation introducer of a second embodiment provided by the present invention;

FIG. 5 is a schematic diagram illustrating the working principle of a vacuum isolation introducer according to a second embodiment of the present invention;

fig. 6 is a schematic diagram illustrating a working principle of a vacuum isolation introducer according to a second embodiment of the present invention.

Reference numerals illustrate:

10. a body; 100. a housing; 101. an ultra-high vacuum chamber; 1011. a first ultra-high vacuum sub-cavity; 1012. the second ultrahigh vacuum sub-cavity; 102. a high vacuum cavity; 110. a sample to be tested; 400. an electron source; 500. a collimation shaping assembly; 700. a valve; 900. a scanning assembly;

20. vacuum isolating the introducer; 210. a flange plate; 220. a motion execution chamber; 221. a receiving chamber; 222. a through hole; 223. a gas feed hole; 224. closing the cavity; 230. a motion guide rod; 231. a rod body; 2311. a magnetic conduction part; 2312. a non-magnetic conductive portion; 232. a piston; 233. a connecting plate; 240. an elastic element; 250. diaphragm bellows; 260. a drive assembly; 261. an excitation power supply; 262. a solenoid coil; 2621. closing magnetic force lines;

30. A vacuum pump assembly; 310. a first stage pump; 320. a second stage pump; 330. an ultra-high vacuum pump; 340. and a bypass valve.

Detailed Description

In order that the above objects, features and advantages of the invention will be readily understood, a more particular description of the invention will be rendered by reference to the appended drawings. In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present invention. The present invention may be embodied in many other forms than described herein and similarly modified by those skilled in the art without departing from the spirit of the invention, whereby the invention is not limited to the specific embodiments disclosed below.

In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings are merely for convenience in describing the present invention and simplify the description, and do not indicate or imply that the device or element being referred to must have a specific orientation, be configured and operated in a specific orientation, and therefore should not be construed as limiting the present invention.

Furthermore, the terms "first," "second," and the like, are used for descriptive purposes only and are not to be construed as indicating or implying a relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defining "a first" or "a second" may explicitly or implicitly include at least one such feature. In the description of the present invention, the meaning of "plurality" means at least two, for example, two, three, etc., unless specifically defined otherwise.

In the present invention, unless explicitly specified and limited otherwise, the terms "mounted," "connected," "secured," and the like are to be construed broadly, and may be, for example, fixedly connected, detachably connected, or integrally formed; can be mechanically or electrically connected; either directly or indirectly, through intermediaries, or both, may be in communication with each other or in interaction with each other, unless expressly defined otherwise. The specific meaning of the above terms in the present invention can be understood by those of ordinary skill in the art according to the specific circumstances.

In the present invention, unless expressly stated or limited otherwise, a first feature "up" or "down" a second feature may be the first and second features in direct contact, or the first and second features in indirect contact via an intervening medium. Moreover, a first feature being "above," "over" and "on" a second feature may be a first feature being directly above or obliquely above the second feature, or simply indicating that the first feature is higher in level than the second feature. The first feature being "under", "below" and "beneath" the second feature may be the first feature being directly under or obliquely below the second feature, or simply indicating that the first feature is less in horizontal height than the second feature.

It will be understood that when an element is referred to as being "fixed" or "disposed" on another element, it can be directly on the other element or intervening elements may also be present. When an element is referred to as being "connected" to another element, it can be directly connected to the other element or intervening elements may also be present. The terms "vertical," "horizontal," "upper," "lower," "left," "right," and the like are used herein for illustrative purposes only and are not meant to be the only embodiment.

As described in the background art, the working principle of the electron microscope is that an electron beam emitted by an electron gun passes through a condenser lens and an objective lens along the optical axis of a lens body in a vacuum channel, and is focused into a light spot to irradiate a sample, and secondary electrons or back scattered electrons generated by the interaction of the electron beam and the surface of the sample or information of the back scattered electrons interacted with a structure in the process of penetrating the sample is collected, so as to obtain the microscopic morphology or composition structure of the surface of the sample. In electron microscopes, as high a vacuum as possible is required in all areas where electrons are running; otherwise, the normal operation of the transmission electron microscope is affected. In order to keep the transmission electron microscope in a high vacuum state all the time, a valve is usually arranged in the electron microscope to isolate vacuum so as to meet the service and test requirements. The motion device driving the valve is typically a vacuum isolation introducer employing linear mechanical motion. In order to facilitate transportation and ensure safety, the vacuum isolation importer of the electron source or the ion source is generally required to be in a pre-loading mode through an elastic element, so that the valve closes the vacuum cavity in a natural state, thereby achieving the purpose of vacuum isolation.

In existing vacuum isolation introducer designs, the spring element is typically mounted in the motion actuator cavity of the vacuum isolation introducer, and has a size, referred to as the compression height of the spring element, due to its minimal size along its axis when in a compressed state. The length of the pre-loaded state of the elastic element determines the length of the cavity of the motion executing mechanism, so that the length of the cavity of the motion executing mechanism is required to meet the motion stroke, and the compression and height of the spring can be accommodated, so that the design of the vacuum isolation importer cannot be miniaturized.

To solve this problem, the structure of the conventional vacuum isolation introducer may be improved, and in particular, it may be considered to remove the elastic element from the motion-performing chamber, so that the pressing and height of the elastic element is not one of factors affecting the length of the vacuum isolation introducer.

Based on the above-mentioned considerations, in order to solve the problem that the design of the existing vacuum isolation importer cannot be miniaturized, the present inventors have conducted intensive studies and have provided a vacuum isolation importer and an electron microscope including a vacuum isolation importer for driving a valve to perform linear and straight movement so that the valve can isolate an area where electrons in the electron microscope are operated, thereby enabling the area to always maintain a high vacuum state. And through setting up motion execution cavity, motion guide arm and elastic element in the vacuum isolation importer, make one end of motion guide arm acceptd in the motion execution cavity, and the other end of motion guide arm stretches out in the motion execution cavity, simultaneously the elastic element is installed in the outside of motion execution cavity, thereby make the pressure and the height of elastic element can not become one of factors that influence importer length, the inside length of motion execution cavity can be equal with the motion stroke, in this way can realize the minimum design of vacuum isolation importer, avoid vacuum isolation importer can take place the interference with other spare part when installing in electron microscope.

The present embodiment is only used as an example and does not limit the technical scope of the present application. It will be appreciated that in other embodiments, the vacuum isolation introducer may be used to push other types of workpieces into linear mechanical rectilinear motion and may be installed in other devices besides electron microscopes, without limitation.

The following describes preferred embodiments of a vacuum isolation introducer and an electron microscope provided by the present application with reference to the accompanying drawings.

The basic structure of an electron microscope is shown in FIG. 1 and includes a housing 10, a vacuum isolation introducer 20, and a vacuum system 30, wherein the housing 10 includes a housing 100, an electron source 300, a collimation shaping assembly 500, a valve 700, and a scanning assembly 900. The housing 100 includes an ultra-high vacuum chamber 101 and a high vacuum chamber 102, and is entirely isolated from the atmosphere. The two cavities are communicated through a small hole, and a valve 700 is arranged on the two cavities and can be opened or closed to cover the small hole; the electron source 300 and the collimation shaping assembly 500 are arranged in the ultra-high vacuum cavity 101, and the collimation shaping assembly 500 comprises a diaphragm for limiting stray electrons, at least one collimation condenser, and shaping components such as an astigmatic device and the like; the scanning assembly 900 is disposed in the high vacuum chamber 102 and includes a focusing objective, a deflector, an imaging detector, and the like, as required for electron beam imaging. In addition, the sample 110 to be measured is also located in the high vacuum chamber 102. The vacuum isolation introducer 20 is used to actuate the opening and closing of the valve 700 to avoid vacuum interactions of the ultra-high vacuum chamber 101 and the high vacuum chamber 102. The vacuum system 30 mainly comprises various vacuum pumps and necessary pipelines and valves to realize and control the vacuum degree of each functional cavity of the electron microscope, thereby meeting the operation requirement of the electron microscope.

The vacuum system 30 includes a first stage (or primary) pump 310 (typically, but not limited to, a mechanical pump) and a second stage (or secondary) pump 320 (typically, but not limited to, a molecular pump) that provide a primary or base vacuum for the high vacuum chamber 102 and the ultra-high vacuum chamber 101. However, this is not sufficient to realize the vacuum degree of the ultra-high vacuum chamber 101, and therefore, the ultra-high vacuum chamber 101 needs to be provided with three or more vacuum pumps to realize the ultra-high vacuum (typically, but not limited to, ion pumps). Due to the high vacuum (vacuum level is usually 1x10 ^-3 ～1x10 ^-7 Torr) to ultra-high vacuum (vacuum degree of 1x10 ^-9 ～1x10 ^-11 ) Is large, must be lifted step by step and stepped. The ultra-high vacuum chamber 101 includes at least one ultra-high vacuum sub-chamber (shown in the figureThere are two, a first ultra-high vacuum sub-chamber 1011 and a second ultra-high vacuum sub-chamber 1012, respectively (depending on the size of the vacuum span, one ultra-high vacuum sub-chamber is generally required to be subdivided for one order of magnitude of vacuum span), each ultra-high vacuum sub-chamber is provided with an independent ultra-high vacuum pump 330 (such as an ion pump or a getter pump), the space between the first ultra-high vacuum sub-chamber 1011 and the second ultra-high vacuum sub-chamber 1012 is also separated by a small hole (but no valve is required to be arranged), thereby realizing and maintaining the vacuum level step by step from the high vacuum chamber 102 (for example, the vacuum level is 1x 10) ^-7 Torr) to a first ultra-high vacuum sub-chamber 1011 (e.g., vacuum level 1x10 ^-8 Torr) to a second ultra-high vacuum sub-chamber 1012 (vacuum level 1x 10) ^-9 Torr). The ultra-high vacuum pump 330 is connected to the vacuum valve 340, commonly referred to as a bypass valve, and connects the first primary pump 310 and the second primary pump 320, so that when the ultra-high vacuum pump 330 is started during the initial vacuum pumping, the bypass valve 340 can be closed, and the vacuum system enters a differential step-by-step vacuum pumping mode. The valve 700 introduced between the ultra-high vacuum chamber 101 and the high vacuum chamber 102 can effectively solve this problem because of the high time and process costs required for the system to go from the high vacuum level to the ultra-high vacuum level. Vacuum isolation introducer 10 is coupled to valve 700 for linear back and forth movement to actuate the opening and closing of valve 700. The action and specific action requirements mainly aim at the following scenes and purposes:

(1) When the electron microscope is in normal use state: at this time, the valve 30 is in an open state, so that the electron beam passes through the valve 30 and reaches the sample, and the subsequent functions of focusing, scanning, imaging detection and the like are completed;

(2) When the electron microscope is in a normal closing state: when the electron microscope does not work, especially when the electron microscope is not used for a long time, the valve 30 is in a closed state so as to reduce the load of the vacuum system;

(3) When the system is abnormal, the system comprises: the system monitors and discovers that the vacuum is abnormal, particularly, the vacuum abnormality occurs in the high vacuum area where the sample is located, the high vacuum area where the electron source is located is generally affected, and at the moment, the system can be in the aim of protecting the ultra-high vacuum cavity to close the valve 30, so that the ultra-high vacuum area is prevented from being affected by depth;

(4) During system maintenance: the system maintenance often involves areas of high vacuum cavity where the sample is located, sometimes even completely exposed to the atmosphere, where the valve 30 must be closed.

Fig. 2 and 3 illustrate a first embodiment of an isolated vacuum introducer 10, including a flange 210, a motion-performing chamber 220, a motion guide 230, a resilient member 240, and a diaphragm bellows 250. The flange 210 has a disc-shaped structure and is fixedly installed on the outer wall of the shell of the electron microscope. The motion execution cavity 220 is fixedly installed at one side of the flange 210 away from the housing of the electron microscope; one end of the motion guide rod 230 is penetrated in the motion execution cavity 220, the other end of the motion guide rod 230 penetrates through the flange 210 and is positioned at one side of the flange 210 far away from the motion execution cavity 220, so that the other end of the motion guide rod 230 is positioned in the shell of the electron microscope and is in a vacuum environment, the end is used for connecting a valve, and the motion guide rod 230 can reciprocate along the axis direction of the motion guide rod 230 relative to the flange 210 under the action of external force; the diaphragm bellows 250 is located at a side of the flange 210 away from the motion-performing chamber 220 such that an outer wall of the diaphragm bellows 250 is also located within the housing of the electron microscope and is in a vacuum environment, one end of the diaphragm bellows 250 is connected to the flange 210, and the other end is connected to an end of the motion guide 230 away from the flange 210. The housing 10 and the diaphragm bellows 250 together isolate the external atmospheric environment from the vacuum environment within the housing 10 of the electron microscope; a resilient member 240 is mounted outside the motion-performing chamber 220 and within the diaphragm bellows 250 for coupling the flange 210 and the motion guide 230, the resilient member 240 being capable of providing a pre-load force that imparts a motion trend to the motion guide 230 from the motion-performing chamber 220 toward the flange 210.

The movement-performing chamber 220 is preferably a hollow cylindrical structure having a receiving chamber 221, and opposite ends of the movement-performing chamber 220 in an axial direction thereof are respectively provided with a through hole 222 communicating the receiving chamber 221 with the outside of the movement-performing chamber 220, the through hole 222 being for the movement guide 230 to pass through the movement-performing chamber 220 and being capable of guiding the linear mechanical movement of the movement guide 230.

Further, in this embodiment, the motion executing chamber 220 is further provided with a gas feed hole 223 at one end of the outer circumferential surface thereof near the flange 210 for feeding high pressure gas, the gas feed hole 223 communicates the external environment with the receiving chamber 221 of the motion executing chamber 220, and when the high pressure gas enters the receiving chamber 221 through the gas feed hole 223, the high pressure gas can drive the motion guide rod 230 to perform linear mechanical motion.

In one embodiment, the motion guide 230 includes a rod 231, a piston 232, and a web 233. The rod 231 is preferably in a long cylindrical structure, the piston 232 is coaxially and fixedly sleeved at one end of the rod 231 along the axial direction thereof, and the connecting plate 233 is coaxially and fixedly sleeved at the other end of the rod 231 along the axial direction thereof. The rod 231 passes through the movement-executing chamber 220 and the flange 210 from through holes formed at opposite ends of the movement-executing chamber 220 in the axial direction thereof, and the rod 231 is coaxially disposed with the movement-executing chamber 220 and the flange 210.

In this way, one end of the rod 231 is inserted into the accommodating cavity 221 of the motion execution cavity 220, and part of the rod 231 is exposed to one end of the motion execution cavity 220 far away from the flange 210, meanwhile, the piston 232 is also accommodated in the accommodating cavity 221 of the motion execution cavity 220, the outer diameter of the piston 232 is equal to the inner diameter of the accommodating cavity 221 of the motion execution cavity 220, so that the piston 232, part of the rod 231 and part of the inner wall of the motion execution cavity 220 jointly form a closed cavity 204, and the gas feeding hole 223 formed in the outer peripheral surface of the motion execution cavity 220 is communicated with the external environment and one side of the piston 232 far away from the closed cavity 204, when high-pressure gas is fed into the accommodating cavity 221 of the motion execution cavity 220 from the gas feeding hole 223, the piston 232 can move along the axial direction of the motion guide rod 230 under the driving of the high-pressure gas so as to reduce the volume of the closed cavity 204; the other end of the rod 231 is located at the side of the flange 210 away from the motion-performing chamber 220 and is located in the housing 10 of the electron microscope.

As shown in fig. 3, the diaphragm bellows 250 is preferably a hollow tubular structure, the outer wall and the inner wall of which are corrugated, and the diaphragm bellows 250 is elastically deformed in the axial direction by the external force, as described above, and the function of the diaphragm bellows 250 is to isolate vacuum from atmosphere, so that the diaphragm bellows 250 is located in the housing 10 of the electron microscope, but the outside of the diaphragm bellows 250 is vacuum, the inside is atmosphere, and the movement guide 230 can move in the atmosphere without resistance when moving in the axial direction thereof due to a certain gap between the movement execution chamber 220 and the flange 210 support.

The elastic element 240 is preferably a spring, and is sleeved on the portion of the rod body 231 of the movement guide 230 extending out of the movement executing cavity 220, and the elastic element 240 is accommodated in the diaphragm bellows 250, specifically, one end of the elastic element 240 is fixedly connected to the flange 210, the other end is fixedly connected to the connecting plate 233 of the movement guide 230, and the elastic element 240 can be in a preloaded state under the action of a preloading force or in a compressed state under the action of an external force.

In an alternative implementation of the first embodiment, the dimension of the elastic element 240 in the axial direction of the movement guide 230 is greater than the dimension of the diaphragm bellows 250 in the axial direction of the movement guide 230, preferably by an amount of 5% -50%, when the elastic element 240 is in the preloaded state. In another alternative implementation of the first embodiment, the resilient element 240 is capable of providing a preload force that is in the range of 0.5 newtons to 150 newtons when the resilient element 240 is in the preloaded state. In yet another alternative of the first embodiment, the pressure gas fed in by the gas feed hole 223 of the movement performing chamber 220 is typically in the range of 0.6Mpa to 0.8Mpa, up to 12.5Mpa. So that the pressurized gas can provide a thrust force that can change the state of the preloaded position. In the above embodiments, the elastic element 240 can apply a sufficient pre-loading force to the valve, and when the motion guide 230 is not in a driving state or the motion guide 230 loses driving energy for some reason and enters a free state, the vacuum isolation introducer 10 can still automatically enter a safe position state corresponding to pre-loading, so that the valve can close the inlet of the ultra-high vacuum chamber tightly, and strict vacuum isolation protection is performed on the ultra-high vacuum chamber.

When the elastic member 240 is in a compressed state, the dimension of the elastic member 240 in the axial direction of the movement guide 230 is also larger than the dimension of the diaphragm bellows 250 in the axial direction of the movement guide 230. At this time, the dimension of the diaphragm bellows 250 in the axial direction of the movement guide 230 has been compressed to the limit minimum dimension, which is the compression and height of the diaphragm bellows 250, and the dimension of the elastic member 240 in the axial direction of the movement guide 230 has not yet been reached, and if there is no restriction of the diaphragm bellows 250, the elastic member 240 can be further compressed to the compression and height, and therefore, the compression and height of the elastic member 240 should be smaller than the compression and height of the diaphragm bellows 250, so that the compression of the diaphragm bellows 250 is not restricted by the elastic member 240 when the movement guide 230 moves in the axial direction thereof in a direction away from the ultra-high vacuum chamber, thereby enabling the movement guide 230 to be sufficiently moved to the limit position in the compressed state, so that the valve can be sufficiently opened when the electron microscope is operating normally.

In this manner, resilient member 240 is removed from motion-performing chamber 220 and installed within diaphragm bellows 250. The inner length of the movement-performing chamber 220 may be equal to the movement stroke of the movement guide 230 without increasing the length of the diaphragm bellows 250. This allows the compression and height of spring element 240 to be less of a factor affecting the length of vacuum isolation introducer 10, enabling a minimized design of vacuum isolation introducer 10.

With continued reference to fig. 2, the vacuum isolation introducer 10 of the first embodiment operates as follows:

when the elastic element 240 is in the pre-loaded state, the dimension of the elastic element 240 along the axial direction of the motion guide rod 230 is the largest, so that the vacuum isolation introducer 10 of the application can support the valve against the inlet of the ultra-high vacuum cavity under the action of the pre-loading force F of the elastic element 240, thereby vacuum isolating the ultra-high vacuum cavity. When high-pressure gas is fed from the gas feed hole 223, the pressure of the fed gas is P, the surface area of the piston 232 on the side away from the closed cavity 204 is S, and the thrust acting on the piston 232 is F _p PS. This force is opposite to the preload force F on the resilient member 240. For example, assuming that the ultimate load of the selected elastic element 240 is 450 newtons, the elastic element 240 is installedThe elastic element 240 is capable of providing a preload force of f=150 newtons when the length after the diaphragm bellows 250 has been precompressed by 1/3, and assuming that the pressure of the high pressure gas is p=0.6 Mpa and the radius of the piston 232 is 15mm, the surface area of the side of the piston 232 remote from the closed chamber 204 is s= 706.5mm ² According to F _p PS, thrust force F generated on piston 232 _p Ps=423 newton, not only less than 450 newton of the limit load of the selected elastic element 240, but also providing a thrust force capable of changing the state of the preloaded position, when F is satisfied _p >F, the movement guide 230 will deviate from the initial position, move away from the ultra-high vacuum chamber along the axial direction of the movement guide 230, reduce the volume of the closed chamber 204, and make the elastic element 240 in a compressed state, at this time, the elastic element 240 can be deformed in a recoverable manner, so that the dimension of the elastic element 240 along the axial direction of the movement guide 230 is minimized, and the valve is opened. When the introduction of the high pressure gas into the movement-performing chamber 220 is stopped, the movement guide 230 moves in the opposite direction by the preload force F of the elastic member 240, so that the elastic member 240 is in the preloaded state, and the size of the elastic member 240 in the axial direction of the movement guide 230 is maximized, thereby opening the valve.

Fig. 4 shows a second embodiment of the vacuum isolation introducer 10 of the present invention, which is similar in construction to the first embodiment, in that the mounting location of the elastic element 240 is the same as that of the elastic element 240 in the first embodiment, and the elastic element 240 is not mounted inside the motion-performing chamber 220, but outside the motion-performing chamber 220, and inside the diaphragm bellows 250, as well as the minimized design of the vacuum diaphragm introducer. The second embodiment differs from the first embodiment in that the vacuum isolation introducer 10 further includes a drive assembly 260, i.e., the motion guide 230 is driven by the drive assembly 260 to move in its axial direction, rather than being driven by feeding high pressure gas.

Specifically, in some embodiments, the driving assembly 260 is an electromagnetic switch element, and includes an excitation power source 261 and a solenoid coil 262 coaxial with the motion guide 230, where the excitation power source 261 is electrically connected to the solenoid coil 262, and the solenoid coil 262 may be housed in a housing cavity 221 of the motion actuator or may be openly fixed to a base (not shown) integral with the flange 210, and when the excitation power source 261 applies a dc excitation current to the solenoid coil 262, according to ampere's law, an axial and radial magnetic field is generated on a closed loop around a cross section of the solenoid coil 262. If only the magnetic field in the paraxial region inside solenoid coil 262 is considered, it has the following characteristics: the direction of the axial field points to a specific side, and the specific direction is determined by the right-hand spiral rule according to the current direction. The direction of the radial magnetic field is mirrored if the axis is used as a reference. If the motion guide 230 is constructed of a ferromagnetic material, it will be magnetized and attracted in a magnetic field. If the motion guide 230 is placed coaxially with the solenoid coil 262, the radial magnetic forces experienced by the motion guide cancel each other out, and only the axial magnetic forces act. Because the ferromagnetic material comprising the motion guide 230 is always reverse magnetized in the magnetic field, the motion guide 230 is always attracted by the magnetic field regardless of the direction of the axial magnetic field, and the force direction is always directed toward the center of the solenoid coil 262.

In this embodiment, the structure of the motion guide 230 is also different from that of the motion guide 230 in the vacuum isolation introducer 10 of the first embodiment, in that the motion guide 230 does not have a piston 232, the motion guide 230 only includes a rod 231 and a connection plate 233, and the connection plate 233 is still sleeved at one end of the rod 231 far from the motion execution cavity 220; the rod body 231 includes a magnetic conductive portion 2311 and a non-magnetic conductive portion 2312, the magnetic conductive portion 2311 is located in the middle of the rod body 231, the non-magnetic conductive portion 2312 is located at two ends of the rod body 231, the two ends of the magnetic conductive portion 2311 are respectively connected with the non-magnetic conductive portion 2312, the magnetic conductive portion 2311 is at least partially exposed out of the motion execution cavity 220 and located at one side of the flange 210 away from the motion execution cavity 220, the magnetic conductive portion 2311 is made of a magnetically soft material such as silicon steel sheet, permalloy and ferrite, and the non-magnetic conductive portion 2312 is made of a magnetically non-magnetically soft material such as copper. The material surrounding solenoid coil 262 in motion-performing chamber 220 may be magnetically permeable soft or non-magnetic. In addition to the difference in magnetic shielding, the main purpose of the motion actuating chamber 220 is to fix the solenoid coil so that the position of the solenoid coil will not be moved by the magnetic field when the solenoid coil 620 generates the magnetic field, and the magnetic conductive portion 2311 of the motion guide 230 will be attracted by the axial electromagnetic force under the action of the magnetic field generated by the solenoid coil 262, the magnitude of the electromagnetic force is proportional to the dc excitation current, and as the excitation increases, the elastic element 240 will compress once the electromagnetic force exceeds the preload force F applied to the motion guide, so that the motion guide 230 can move in the direction approaching the motion actuating chamber 220, thereby achieving the purpose of opening the valve.

It should be noted that the driving assembly 260 is not limited to an electromagnetic switch element composed of the excitation power source 261 and the solenoid coil 262, and any moving member capable of driving the movement guide 230 to move in the direction of its own axis is not limited herein.

Thus, the second embodiment of the vacuum isolation introducer 10 described above operates as follows:

as shown in fig. 4, in the initial state, the exciting current is zero, the motion guide 230 is in a pre-loaded state under the action of the pre-loading force F of the elastic element 240, and at this time, the motion guide 230 abuts the valve against the inlet of the ultra-high vacuum chamber, and the valve is closed. The solenoid coil 262 generates a magnetic field when the excitation power 261 applies a dc excitation current, and the magnetic field forms a closed magnetic line 2621 as shown by a dotted line in fig. 4, so that electromagnetic force is generated on the magnetic conductive portion 2311 of the motion guide 230, and electromagnetic force acting on the motion guide 230 has electromagnetic force vectors in two directions: first magnetic force F along axial direction of motion guide 230 _m And a second magnetic force F along the radial direction of the movement guide 230 _n Because the motion guide 230 and the solenoid coil 262 are axially symmetrically arranged, a second magnetic force F is generated along the radial direction of the motion guide 230 _n Always on the other side of symmetry there is another opposite second magnetic force F _n The two are acting on the same entity but in opposite directions so as to be mutually offset, so that only a first magnetic force F remains along the axial direction of the movement guide 230 and opposite to the preload force F of the elastic element 240 _m . And because the solenoid 262 is fixed, the guide rod is moved230 are movable and the linear driving function of the movement guide 230 can be achieved. According to the electromagnetic field principle, the radial electromagnetic force applied to the motion guide 230 is proportional to the magnetic field generated by the solenoid coil 262, and the magnetic field generated by the solenoid coil 262 is proportional to the applied exciting current, so that Fm can be satisfied when the exciting current is increased to a certain threshold value>F, thereby being able to change the closed state of the valve pushed by the end of the motion guide 230.

At this time, as shown in fig. 5, the movement guide 230 can deviate from the initial position to move toward the direction approaching the movement executing cavity 220 to reach the stable position under the action of the first magnetic force Fm along the axial direction of the movement guide 230, so that the elastic member 240 is in a compressed state, the axial force of the movement guide 230 reaches equilibrium, and the valve is opened at this time, thereby realizing the position control of the valve. In a preferred embodiment, the ampere-turns of solenoid coil 262 satisfy a magnetic force output on motion guide 230 of between 1 newton and 450 newtons.

The vacuum isolation introducer 10 of the embodiment drives the motion guide rod 230 to move by feeding high-pressure gas and electromagnetic excitation respectively to realize automatic control of the valve position, and the valve is not required to be controlled manually, so that the control mode is simpler and more convenient, and accurate control of the valve position is realized.

It should be noted that the vacuum isolation introducer 10 of the above embodiment may also be used to adjust the preload force F by selecting different spring elements 240 and selecting different amounts of precompression, thereby setting the threshold of force required to change the position.

The technical features of the above-described embodiments may be arbitrarily combined, and all possible combinations of the technical features in the above-described embodiments are not described for brevity of description, however, as long as there is no contradiction between the combinations of the technical features, they should be considered as the scope of the description.

The above examples illustrate only one embodiment of the invention, which is described in more detail and is not to be construed as limiting the scope of the invention. It should be noted that it will be apparent to those skilled in the art that several variations and modifications can be made without departing from the spirit of the invention, which are all within the scope of the invention. Accordingly, the scope of the invention should be assessed as that of the appended claims.

Claims

1. A vacuum isolation introducer, comprising:

a flange (210);

a movement execution cavity (220) fixedly installed at one side of the flange plate (210);

one end of the motion guide rod (230) penetrates through the motion execution cavity (220), the other end of the motion guide rod penetrates through the flange plate (210), the other end of the motion guide rod (230) is positioned at one side, far away from the motion execution cavity (220), of the flange plate (210), and the motion guide rod (230) can reciprocate along the axis direction of the motion guide rod relative to the flange plate (210) under the action of external force; a kind of electronic device with high-pressure air-conditioning system

And an elastic element (240) with one end connected to the flange plate (210) and the other end connected to an end of the movement guide rod (230) away from the movement execution cavity (220), wherein the elastic element (240) can provide a pre-loading force for enabling the movement guide rod (230) to have a movement trend pointing from the movement execution cavity (220) to the flange plate (210).

2. The vacuum isolation introducer of claim 1, wherein the resilient element (240) is capable of being in a preloaded state under the force of the preload or in a compressed state under an external force;

-the dimension of the elastic element (240) in the axial direction of the movement guide (230) is maximum when the elastic element (240) is in the preloaded state; when the elastic element (240) is in the compressed state, the elastic element (240) is capable of undergoing a restorable deformation to minimize the dimension of the elastic element (240) along the axial direction of the motion guide (230).

3. The vacuum isolation introducer of claim 1, wherein the vacuum isolation introducer (10) further comprises a diaphragm bellows (250), one end of the diaphragm bellows (250) is fixedly connected to the flange plate (210), the other end of the diaphragm bellows (250) is fixedly connected to the movement guide rod (230), and the elastic element (240) and the movement guide rod (230) are partially accommodated in the diaphragm bellows (250).

4. A vacuum isolation introducer according to claim 3, wherein the diaphragm bellows (250) is capable of restorable deformation along the axial direction of the movement guide (230), the elastic element (240) having a larger dimension along the axial direction of the movement guide (230) than the diaphragm bellows (250) has along the axial direction of the movement guide (230).

5. The vacuum isolation introducer of claim 2, wherein an end of the motion guide rod (230) received within the motion execution chamber (220) defines a closed chamber (224) with a portion of an inner wall of the motion execution chamber (220).

6. The vacuum isolation introducer of claim 5, wherein the motion execution chamber (220) is provided with a gas feed hole (203) for introducing high-pressure gas, and the gas feed hole (203) communicates with the external environment and one end of the motion guide rod (230) accommodated in the motion execution chamber (220);

The high-pressure gas can drive the motion guide rod (230) to move along the axis direction thereof through the gas feed hole (203) so as to reduce the volume of the closed cavity (224) and enable the elastic element (240) to be in the compressed state.

7. The vacuum isolation introducer of claim 2, wherein the vacuum isolation introducer (10) comprises a drive assembly (260), the drive assembly (260) being at least partially housed within the motion-performing cavity (220), the drive assembly (260) being configured to drive the motion guide (230) in a direction of its own axis to place the resilient element (240) in the compressed state.

8. The vacuum isolation introducer of claim 7, wherein the drive assembly (260) comprises an excitation power source (261) and a solenoid coil (262), the excitation power source (261) being electrically connected to the solenoid coil (262), the solenoid coil (262) being housed within the motion-performing cavity (220) and nested within a portion of the motion guide (230), the excitation power source (261) being configured to generate an excitation current to cause the solenoid coil (262) to generate a magnetic field for driving the motion guide (230) to move.

9. The vacuum isolation introducer of claim 8, wherein the motion guide (230) comprises a magnetically permeable portion (2311), the magnetically permeable portion (2311) is at least partially exposed to the motion-performing chamber (220) and is located on a side of the flange (210) away from the motion-performing chamber (220), the magnetically permeable portion (2311) and the motion-performing chamber (220) are made of soft magnetic materials, and the magnetic field generated by the solenoid coil (262) can drive the magnetically permeable portion (2311) to move along an axial direction of the motion guide (230) toward a direction approaching the motion-performing chamber (220) so as to place the motion guide (230) in the compressed state.

10. An electron microscope comprising a valve (700) and a vacuum isolation introducer (10) according to any of claims 1 to 9, said valve (700) being mounted at one end of said vacuum isolation introducer (10); the electron microscope is also provided with an ultra-high vacuum cavity (101), and the vacuum isolation importer (10) can drive the valve to reciprocate along the axial direction of the vacuum isolation importer (10) so as to open or close the ultra-high vacuum cavity (101).