503 results about "Secondary electrons" patented technology

The invention discloses an ionization chamber internal electric field modeling and radioactive interference suppression method. The method comprises the following steps: modeling by adopting a multi-physical simulation software package to obtain a geometric model of an ionization chamber; analyzing electric field distribution in the ionization chamber through finite element analysis software, and simulating a plurality of parameters by adopting a particle physical experiment simulation program to set a drift trajectory and a drift end point of secondary electrons so as to obtain ionization chamber parameters meeting conditions; and optimizing the ionization gas chamber according to the ionization gas chamber parameters meeting the conditions, and monitoring and outputting particle drift and current induction results based on the optimized ionization gas chamber. The radiation interference caused by the detector can be shielded on the basis of the original functions of the traditional ionization gas chamber, and the background emissivity of the alpha particle measuring device is reduced, so that the detection efficiency and accuracy of low-level radioactive measurement are improved.

The invention provides a material characterization image analysis system and an analysis method thereof. The invention discloses a material characterization image analysis system and an analysis method thereof, and the method comprises the following steps: S1, obtaining a back scattering electron image, a secondary electron image and energy spectrum data of a material through a scanning electron microscope, and dynamically adjusting the acceleration voltage, beam current and detector gain of the scanning electron microscope through a parameter optimization algorithm based on a preset material type and an observation target; s2, carrying out multi-scale feature enhancement preprocessing on the back scattering electron image and the secondary electron image, wherein the preprocessing comprises noise suppression, non-uniform illumination correction and micro-area texture enhancement; s3, pixel-level space registration is carried out on the back scattering electron image and the energy spectrum element distribution diagram, and a multi-modal fusion feature matrix is constructed. The material characterization image analysis system and the analysis method thereof provided by the invention have the advantages that the distortion problem can be well solved, the micro-structure identification accuracy can be improved, and the life prediction error can be reduced.

Systems and methods of forming images of a sample using a multi-beam apparatus are disclosed. The method may include generating a plurality of secondary electron beams from a plurality of probe spots on the sample upon interaction with a plurality of primary electron beams. The method may further include adjusting an orientation of the plurality of primary electron beams interacting with the sample, directing the plurality of secondary electron beams away from the plurality of primary electron beams, compensating astigmatism aberrations of the plurality of directed secondary electron beams, focusing the plurality of directed secondary electron beams onto a focus plane, detecting the plurality of focused secondary electron beams by a charged-particle detector, and positioning a detection plane of the charged-particle detector at or close to the focus plane.

A control device controls a contact probe in synchronization with a pulse-controlled light having a predetermined wavelength, a measurement instrument measures a characteristic of a sample to be inspected or an analysis sample, and a circuit constant or a defect structure of the sample to be inspected is estimated based on a circuit model created by an electric characteristic analysis device configured to generate the circuit model based on a value measured by the measurement instrument and a detection signal of secondary electrons detected by the charged particle beam device.

The invention provides a multistage depressed collector for an ultra wide band traveling wave tube. The multistage depressed collector comprises an insulating porcelain cylinder with an inner cavity, an inner collector accommodated and fixed in the inner cavity of the insulating porcelain cylinder, and an outer collector fixedly arranged on the outer wall of the insulating porcelain cylinder, the inner collector comprises a preceding-stage collector and a final-stage collector which are arranged along the axial direction of the insulating porcelain cylinder; the preceding-stage collector comprises a top wall part, a through hole for an electron beam to pass through is formed in the top wall part, and the surface of one side, facing the last-stage collector, of the top wall part comprises a protruding structure protruding towards the last-stage collector. The collector can effectively restrain reflection of secondary electrons, reduce the electron backflow rate, achieve high recovery efficiency and improve the efficiency of the ultra-wideband traveling wave tube.

The invention discloses a scanning electron microscope analysis method for inclusions in rare earth steel. The scanning electron microscope analysis method comprises the following steps: (1) marking the inclusions under a metallographic microscope by adopting a coordinate method; (2) observing the inclusions in the rare earth steel by a scanning electron microscope; (2.1) analyzing the principle of the rare earth inclusions by a scanning electron microscope; the method comprises the following steps: determining the position of the rare earth inclusion in a back scattering mode, then switching to a secondary electron mode to observe the morphology details, and analyzing the components in combination with an energy spectrum; and (2.2) a scanning electron microscope analysis method, wherein a scanning electron microscope is used to carry out further morphology and component analysis on typical inclusions observed under a metallographic microscope. Typical inclusions in the rare earth steel are marked under a metallographic microscope by adopting a coordinate method, and the target inclusions can be quickly found to carry out corresponding detection analysis by utilizing the working principle of a scanning electron microscope, so that the detection analysis efficiency is greatly improved, and researchers are assisted to quickly and accurately obtain related detection results of the rare earth inclusions.

PURPOSE: To relate to a multi-beam image generating device and a multi-beam image generating method that rapidly acquire images by generating multiple primary electron beams while maintaining a sample in a horizontal position, irradiating the sample with these beams while moving the sample, separating the multiple secondary electron beams with a beam splitter, detecting information on respective images with an electron detection device to synthesize a single image.CONSTITUTION: A multi-beam image generating device includes a multiple beam generating device, a beam splitter, an objective lens, a deflection system, a projection lens, a stage, and height measuring means, and is configured to make multiple primary electron beams incident on the axis of the objective lens via the beam splitter while the stage is maintained horizontal on the basis of the sample height output from the height measuring means, radiate the finely focused primary electron beam and scan with the deflection system, make secondary electrons emitted from the sample incident on the axis of the projection lens via the beam splitter, and form images to output image information of the multiple electron beams.SELECTED DRAWING: Figure 19

In a method for inspecting pattern defects, a plurality of patterns are formed over an underlying layer. The plurality of patterns are electrically isolated from each other. A part of the plurality of patterns are scanned with an electron beam to charge the plurality of patterns. An intensity of secondary electrons emitted from the scanned part of the plurality of patterns is obtained. One or more of the plurality of patterns that show an intensity of the secondary electrons different from others of the plurality of patterns are searched.

The invention discloses a high-power pulse magnetron cathode, and belongs to the technical field of magnetrons. The cathode comprises a heating substrate, an upper end cap, a lower end cap and a cathode emitter, the upper end of the heating substrate is connected with the upper end cap, and the lower end penetrates through the lower end cap and extends out of the magnetron tube core to be connected with a power supply; the heating substrate positioned between the upper and lower end caps is spiral-line-shaped; and the cylindrical cathode emitter is sleeved on the outer side of the spiral linear part of the heating substrate. The cathode emitter is heated through the heating substrate, so that the cathode emitter emits electrons, and the emitted electrons back bomb the surface of the cathode emitter under the action of an external electromagnetic field of the magnetron to generate new secondary electrons. According to the invention, the probability of electron bombardment on the surface of the cathode emitter can be greatly increased, that is, secondary emission electrons can be bombarded continuously, the overall electron emission density of the cathode is improved, and a high-power pulse magnetron is supported to provide higher power output.

The invention relates to an ultrafast electron microscopic imaging device and an imaging method thereof, in particular to a multi-mode multi-dimensional ultrafast electron microscopic imaging device and an imaging method thereof, and solves the problem that the existing electron microscopic imaging technical scheme is difficult to simultaneously meet the measurement requirements of high time-space-energy-momentum resolution and material diversification. The device comprises a sample cabin, an electron gun, a laser generation module, a secondary electron detector, an STEM detector, an in-cabin plug-in detection assembly, a plug-in camera and an energy filtering electron microscope assembly which are arranged below the sample cabin, and a vacuum system, a hollow sample table is arranged in the sample cabin, and at least two ultrafast pumping laser introduction windows are arranged on the cabin wall of the sample cabin; an ultrafast detection laser introduction window is arranged on the electronic gun shell; the secondary electron detector is arranged obliquely above the sample table; the STEM detector is arranged on the side cabin wall of the sample cabin and is positioned below the sample table; and the in-cabin plug-in detection assembly is arranged below the STEM detector.

An apparatus comprises: a focused ion beam (FIB) column within a vacuum chamber configured to direct ions comprising a mixture of protons and non-hydrogen ions onto a sample, wherein the kinetic energy of ions of the mixture is not greater than 50 kilo-electron-Volts (keV); and an X-ray detector configured to detect and measure X-rays that are emitted from the sample in response to the impingement of the protons and non-hydrogen ions onto the sample. The apparatus may further comprise an electron microscope column within the vacuum chamber configured to direct and focus a beam of electrons onto the sample and to detect secondary electrons or backscattered electrons that are emitted from the sample in response to the impingement of the beam of electrons onto the sample. The electron microscope may generate an image of a sample area that is milled by the FIB column.

The invention relates to the field of mass spectrum equipment, in particular to a low-noise and high-sensitivity mass spectrometer Faraday cup. The Faraday cup comprises a rectangular housing, one side of which is open; the suppression grid is arranged in the shell and is close to the opening; the collector is arranged in the shell and is adjacent to the suppression grid; a slit baffle is arranged at the opening of the shell; the collector is fixed through the insulating lining, insulated from the shell, and used for receiving the ion beam and generating current; the suppression grid electrode is fixed through an insulating lining and a metal positioning block, and negative bias voltage is applied to suppress escape of secondary electrons; the top cover is assembled on the shell to form a sealed whole; the collector connecting piece is arranged on the lower portion of the collector, one end of the Faraday cup outgoing line is welded to the collector connecting piece, and the other end of the Faraday cup outgoing line is led out of the shell. Noise is remarkably reduced, and the detection sensitivity of a mass spectrometer is improved.

The invention discloses polyimide with high surface electric strength based on surface natural microporous structure regulation and a preparation method and application thereof, and belongs to the technical field of high-voltage insulating materials. Dried diamine is dissolved in a solvent A, dianhydride is added, and after uniform stirring, a polyamide acid solution is obtained; adding a pore-forming agent, and stirring at a high speed until the mixture is uniformly dispersed to obtain a mixed viscous solution C; after coating, drying, imidization high-temperature heating and natural cooling, immersing into the liquid B to extract the pore-forming agent, and drying to obtain the high-surface electric strength polyimide based on surface natural microporous structure regulation and control. The surface of the polyimide has a natural porous structure, the surface is a surface along an electric field and a through hole structure densely distributed along the surface of the electric field, and electrons are easy to fall into the through hole structure and are difficult to return to the surface in a jump multiplication process during flashover, so that a secondary electron multiplication process is inhibited, the probability of forming secondary electron collapse is reduced, and the flashover effect is improved. Therefore, the along-surface electric strength is improved.

This inspection system 100 comprises: an electron source 102 which irradiates a sample 200 with an inspection beam; a detector 105 which detects secondary electrons obtained by irradiating the sample 200 with the inspection beam and outputs a detection signal; a laser device 107 which emits an action laser that changes the amount of secondary electrons; an electron gun 106 which emits an action electron beam that changes the amount of secondary electrons; and a computer system 140 which generates an image of the sample 200 on the basis of the detection signal. The computer system 140 generates an inspection image I1 related to the emission of the inspection beam, acquires the dimensions and the like related to a pattern on the sample 200 on the basis of the inspection image I1, generates an inspection image I2 related to the emission of the action laser and the inspection beam, acquires the material characteristics related to the pattern on the basis of the inspection image I2, generates an inspection image I3 related to the emission of the action electron beam and the inspection beam, and acquires the electrical characteristics related to the pattern on the basis of the inspection image I3.

The utility model relates to the technical field of X-ray tubes, in particular to an X-ray tube with high-stability luminous flux, which comprises a tube shell, a cathode assembly, an anode assembly and a window assembly, and is characterized in that the anode assembly comprises an anode cap, an anode rod and an anode target assembly; the anode cap comprises an expansion part, a partition part and a necking part which are sequentially connected in the axial direction of the anode cap, the expansion part wraps the focusing piece from the bottom and the circumferential direction of the focusing piece, an electron beam incidence hole is formed in the partition part, and a packaging cavity extending in the axial direction and an X-ray outlet penetrating in the radial direction are formed in the necking part; the potential of the anode assembly is higher than that of the cathode assembly; along the axial direction of the X-ray tube, the distance H between the bottom of the focusing part and the top of the expansion part is greater than the distance D1 between the bottom of the focusing part and the partition part, so that stray electrons and secondary electrons generated by the stray electrons and overflow electrons and secondary electrons generated by the overflow electrons are absorbed after repeated back bombardment in the expansion part, and the secondary electrons are completely prevented from bombarding a tube shell, thereby improving the efficiency of the X-ray tube. And the high stability of the X-ray luminous flux is ensured.

A method of operating a charged particle beam apparatus is described. The method includes guiding a primary charged particle beam through an opening of an on-axis detector, through an intermediate lens, through an objective lens, and onto a specimen, wherein the intermediate lens is disposed between the on-axis detector and the objective lens; focusing the primary charged particle beam with the objective lens onto the specimen; in a first mode of operation, providing an excitation of the intermediate lens to collimate high energy signal electrons including backscattered electrons to the opening of the on-axis detector; in the first mode of operation, detecting low energy signal electrons including secondary electrons with the on-axis detector; and in the first mode of operation, detecting the backscattered electrons with a second electron detector upstream of the on-axis detector. Also a corresponding charged particle beam apparatus is described.

The invention discloses a method for measuring first electron affinity of a semiconductor film material, which belongs to the field of surface interface analysis and comprises a calibration step, a test step and a calculation step. According to the method, a vacuum ultraviolet light electron energy spectrum system and a reflective electron energy spectrum system are carried in a main ultrahigh vacuum chamber, and an ultraviolet light electron energy spectrum technology and a reflective electron energy spectrum technology are combined, so that a secondary electron cut-off side energy position and a work function relative to a Fermi level can be obtained; in addition, the position of the conduction band bottom or the position of the lowest unoccupied molecular orbital can be obtained, the first electron affinity value of the semiconductor film material can be further obtained through calculation, and the measurement method is convenient, simple in operation process, high in accuracy and high in universality.

A method for dynamic aberration correction includes generating a primary electron beam with an electron beam source. The method includes directing the primary electron beams to a sample with an electron-optical column and deflecting the primary electron beam to an objective lens of the electron-optical column using a first Wien filter to correct for coma blur in the primary electron beam. The method includes generating off-axis chromatic aberration in the primary electron beam using the objective lens. The method includes adjusting one of a strength or orientation of the Wien filter to correct the off-axis chromatic aberration in the primary electron beam generated by the objective lens. The method includes detecting one or more secondary electrons emanating from the sample.

The invention relates to the technical field of nuclear physics, particle physics and nuclear celestial body physics experiments, in particular to a position-sensitive flight time detector and a use method thereof. The flight time detector comprises a detector field cage which is provided with an emission film used for generating secondary electrons and a high-voltage wire mesh used for providing an electric field required for guiding the secondary electrons; the delay line reading plates are arranged above the emission film in parallel at intervals; the conical anode readout is arranged below the emission film in parallel at intervals; the delay line read-out plate and the conical anode read-out plate are respectively provided with an MCP assembly on one side facing the emission film. The MCP assembly cooperates with the delay line readout plate to provide location information, and the MCP assembly cooperates with the tapered anode readout to provide time information. According to the flight time detector, a position reading part and a time reading part are combined, time resolution and position resolution can be independently optimized, and the structure can be compact.

The invention provides a method for inhibiting micro discharge of a space traveling wave tube, which comprises the space traveling wave tube and comprises the following steps of: depositing an aluminum oxide film on the surface of a ceramic original sample by adopting an alternating action mode of a plurality of precursors; the ceramic original sample is that no film is deposited on the ceramic surface of the space traveling wave tube. The various precursors are trimethylaluminum and water; the deposition temperature is 250 DEG C to 350 DEG C. According to the method, the secondary electron emission coefficient of the surface of the ceramic original sample is reduced and the flashover voltage along the surface is improved by depositing the aluminum oxide thin film on the surface of the ceramic original sample, so that the probability of micro discharge of the space traveling wave tube is reduced, and the method has a relatively good application prospect in the aspect of solving the micro discharge of the space traveling wave tube; the method has important application value for improving the reliability of the space traveling wave tube in the spacecraft.

The invention discloses a high-power pulse magnetron cathode heater assembly, a preparation method and an application. The preparation method comprises the following steps: winding a tungsten filament, and sequentially carrying out primary high-temperature shaping, insulating layer coating and secondary high-temperature sintering to prepare a required heater; preparing a cathode blank with a tantalum sponge body; preparing a cathode prefabricated part with the tantalum sponge body; coating the composite rare earth oxide turbid liquid, and sintering in a high-temperature vacuum furnace to obtain the required cathode; and assembling the cathode and the heater, filling the space between the cathode and the heater with a heat-conducting and electric-conducting material, and sintering in a vacuum furnace to prepare the cathode and heater assembly. The cathode heater assembly has high heat emission and secondary electron emission, has good electron and ion bombardment resistance, prolongs the service life, and can adapt to the working environment of a high-power pulse magnetron; and the device also has the characteristics of low cathode heating power, high thermal emission current density and the like, and can be quickly started.

The invention discloses a three-dimensional atom probe with high ion detection efficiency. The three-dimensional atom probe comprises a tip sample, a surface treatment substance evaporation source and an ion detector, the ion detector comprises a flaring microchannel plate group subjected to surface evaporation treatment and a position-sensitive anode, the surface evaporation treatment process comprises the steps that the ion detector and the evaporation source are installed in the three-dimensional atom probe, and after vacuumizing, the evaporation source is heated to excite the low-work-function material to conduct surface evaporation treatment on the ion detector for 1-10 min. According to the three-dimensional atom probe, on the basis of the synergistic effect of all the components, the emission coefficient of ions colliding with secondary electrons is effectively improved, the ion conversion efficiency and the detection precision of the three-dimensional atom probe are greatly improved, through tests, the detection efficiency of a detector of the three-dimensional atom probe on ions is larger than or equal to 95%, the overall detection efficiency on the ions reaches 90% or above, and the detection efficiency of the three-dimensional atom probe on the ions is greatly improved. Compared with the prior art, the overall detection efficiency is improved by about 20%.

Disclosed is a radiation and magnetic field generating apparatus irradiating photon beam radiation to in-body affected tissue of a subject including a radiation generating unit that irradiates the photon beam radiation to the subject and induces generation of secondary electrons in an area of the subject where the photon beam radiation is irradiated, a magnetic field generating unit, which is provided to be inserted into a body, which includes an insertion structure for forming a low-density space, and which forms a magnetic field in an area in which the secondary electrons are generated, and a synchronization control unit that controls formation of the magnetic field such that a part of the secondary electrons moves to the low-density space based on a relationship between an area where the photon beam radiation is irradiated and a location of an affected part, and controls the formation of the magnetic field.

Provides is an ultra-microlight transmission device using secondary electrons according to various embodiments of the present invention for implementing the above-objects. The ultra-microlight transmission device includes a light source module configured to generate light, a housing which includes an interior space and performs spectroscopy and diffuse reflection on light introduced into the interior space, a first filter unit configured to convert the spectroscopic and diffusely reflected light into monochromatic light, and a second filter unit configured to cause diffraction and interference for the converted light.

The invention discloses a design and preparation method of an alumina ceramic insulating part for vacuum, which belongs to the technical field of design and preparation of ceramic insulating parts, and comprises the following steps of: optimizing and regulating along-surface electric field distribution by a macrostructure, optimizing and regulating secondary electron multiplication by a microstructure, and the like. According to the method, integrated optimization design and model construction are carried out by integrating the starting stage and the development stage of vacuum surface flashover, generation of initial electrons is effectively reduced, multiplication of secondary electrons is inhibited, the electric strength of a whole insulation system is greatly enhanced, and the stability of equipment is remarkably improved; according to the method, a ceramic 3D printing photocuring layer-by-layer printing mode is adopted, additional machining or mold manufacturing is not needed, a 3D printer adopting an ultraviolet digital forming technology is combined with a sintering furnace, and an aluminum oxide ceramic component with a complex shape and a delicate pattern can be directly and integrally generated from computer graphic data, so that the development period of a product is greatly shortened, and the production cost is reduced. The production efficiency is improved, and the production cost is reduced.

The invention discloses a method and a system for improving secondary electron collection efficiency in a rejection field scanning electron microscope. The method comprises the following steps: acquiring a new straight optical axis condition of a Wien filter when an edge electromagnetic field is not matched; under the new straight optical axis condition, the influence rule of the orientation angle and excitation of the Wien filter on the primary electron transmission characteristic is obtained; determining the position and the size of a secondary electron emission source; according to the position and the size of a secondary electron emission source and the influence rule of the orientation angle and the excitation of the Wien filter on the transmission characteristics of the primary electrons, the excitation and the orientation angle of the Wien filter required when the secondary electrons are completely collected are calculated.

Provided are: a hydrogen separation filter which has a high hydrogen permeation rate and which prevents or reduces separation between layers; and a method for producing the hydrogen separation filter. The hydrogen separation filter includes a porous substrate and a palladium layer provided on the porous substrate. The grain boundary number density observed in a cross-sectional secondary electron image of the palladium layer is 1-5 grains / [mu] m. A method for manufacturing a hydrogen separation filter includes forming a palladium layer on a porous base material by a sputtering method while keeping the temperature of the porous base material at 300-600 DEG C.

The present invention discloses a method for controlling the surface potential of an insulating material under high vacuum, which uses an ultraviolet light source to irradiate an insulating material sample to generate radiation-induced conductivity, and discharges the charge by discharging the charge to the ground. In the present invention, an ultraviolet light source is used to irradiate an insulating material sample to generate radiation-induced conductivity, and discharges the charge by discharging the charge to the ground, which can effectively eliminate the surface potential formed by the accumulated charge on the surface of the insulating material sample, without the need to additionally equip expensive equipment such as electron guns and ion sources, thereby reducing the cost of potential control, eliminating complex external circuit design, and increasing test reliability; ultraviolet irradiation is used to achieve surface potential control of the insulating material under high vacuum conditions, and the surface potential neutralization operation can be completed without contacting the sample surface, thereby avoiding damaging the sample surface morphology and thus affecting its secondary electron emission characteristics, increasing test stability, and improving the accuracy of secondary electron emission coefficient measurement.

A method of identifying defective electrical connections of a substrate is provided, the substrate having a first surface contact and a first electrical connection extending from the first surface contact through the substrate. The method includes placing the substrate on a stage in a vacuum chamber; charging the first surface contact by directing an electron beam on the first surface contact and detecting secondary electrons emitted from the first surface contact during the charging for determining a secondary electron signal over time; and determining a state information about the first electrical connection depending on an occurrence of a drop or decline in the secondary electron signal. Further described is an apparatus for identifying defective electrical connections of a substrate according to the methods described herein.

The invention relates to the technical field of high-current particle beam diagnosis, in particular to a high-energy ion beam three-dimensional reconstruction method and system based on secondary electron emission signals. According to the technical scheme, the method comprises the steps of data preprocessing and conversion, geometric space up-sampling, point assignment generation and model boundary division and output. According to the method, the spatial sparsity of original data is overcome through geometric upsampling, the fidelity of physical attribute reconstruction is remarkably improved by utilizing a topological structure based on a minimum spanning tree and a primary function frequency superposition model, automatic and accurate division of beam boundaries is realized according to a physical threshold value, an end-to-end automatic processing flow is formed, and the method has the advantages that the method is simple and convenient to operate and high in practicability. And outputting a visual three-dimensional model supporting interactive analysis, systematically solving the problems of data sparsity, interpolation distortion and boundary fuzziness in the prior art, and realizing high-precision and high-efficiency reconstruction and visual analysis of the three-dimensional form of the high-energy ion beam.