• An electron beam is drawn from the filament and accelerated across the region in which the ions are formed and toward the electron trap. (britannica.com)
  • This electron-beam evaporation system deposits the coatings. (anl.gov)
  • Small nanoparticles are prone to agglomerate under intense bombardment from the electron beam. (rsc.org)
  • Introduction The Thermionics Laboratory e-GunTM, an electron beam evaporation source, is used to produce uniform high-purity films and optical coatings. (thermionics.com)
  • The ground system is a very important aspect of the installation of the electron beam equipment. (thermionics.com)
  • Here, we report the fabrication of diamond nano-pillars with diameters up to 1000 nm by electron beam lithography and inductively coupled plasma reactive ion etching in nitrogen-rich diamonds (type Ib) with [100] and [111] crystal orientations. (mdpi.com)
  • Because the secondary electron spin polarization is proportional to the magnetization in the area probed by the incident electron beam, the magnetization is measured directly, independent of topographic contrast. (nist.gov)
  • Like the SEM, the EPMA uses a primary electron beam to stimulate signal emission. (ou.edu)
  • Chemical analysis with the EPMA is performed by the detection and counting of fluorescent x-rays that are produced by electron transitions (from outer to inner orbitals) in atoms of the sample, the transitions being stimulated by electron bombardment (by the primary beam). (ou.edu)
  • They found that the HRTEM electron beam generates free radicals that degrade the sample's molecular structure. (materialstoday.com)
  • O. Hahn and F. Strassmann have discovered a new type of nuclear reaction, the splitting into two smaller nuclei of the nuclei of uranium and thorium under neutron bombardment. (todayinsci.com)
  • Gem suppliers use a neutron bombardment method in a nuclear reactor to produce the London Blue Topaz. (mygemologist.com)
  • Neutron bombardment in a nuclear reactor produces the deep slightly greenish or greyish London Blue, while electron bombardment in a linear accelerator results in the light aqua-like blue, known as sky blue. (bwsmigel.info)
  • If neutron bombardment has been used, there is residual radioactivity, and the gems must be held, up to a year, before they have "cooled" enough to be worn. (bwsmigel.info)
  • This issue is also discussed regarding reflection high-energy electron diffraction measurements in the growth procedure [ 2 ]. (springer.com)
  • Surface science techniques: low energy electron diffraction (LEED), reflection high energy electron diffraction (RHEED), Auger electron spectroscopy, secondary ion mass spectroscopy (SIMS), sample preparations in UHV, molecular beam epitaxy (MBE), positron annihilation-induced Auger electron spectroscopy (PAES). (infim.ro)
  • The recent development of scanning electron microscopy with polarization analysis (SEMPA) has made the direct measurement of magnetic structures with submicron spatial resolution possible. (nist.gov)
  • Arc welders' pneumoconiosis: studies with advanced techniques of scanning electron microscopy and microprobe analysis. (cdc.gov)
  • Tissues were prepared for scanning electron microscopy (SEM) using standard methods. (cdc.gov)
  • Scanning Electron Microscopy. (bvsalud.org)
  • Electron impact has remained the most widely used method of ionization in mass spectrometry. (britannica.com)
  • Ionization of gas by collision with electrons. (thermionics.com)
  • Electron ionization can be used for some voltatile organometallics. (jeolusa.com)
  • Fast atom bombardment (FAB) and electrospray ionization (ESI) are useful provided suitable solvents can be used. (jeolusa.com)
  • If the magnetic field lines cross the anode, a large portion of hot electrons will be collected at the anode and won't take part in the ionization of the xenon atoms, resulting in high discharge current, low ionization degree, and consequently, low performance level. (sciencedaily.com)
  • He won the Nobel Prize for Physics in 1925 for his work on the excitation and ionization of atoms by electron bombardment. (germanculture.com.ua)
  • Lung tissues were also studied via microbeam or microprobe analysis (MPA), which consists of the spectrophotometric detection of the electromagnetic energy released in the X-ray wavelength by the bombardment of a target with electrons. (cdc.gov)
  • It is an important tool to evaluate the surface quality which has to fulfil high demands in case of quantifications by electron microprobe analysis. (mpg.de)
  • Plasma refers to an ionized gas containing an approximately equal number of positive ions and electrons. (britannica.com)
  • The gap left behind is surrounded by positively charged calcium ions, and strongly attracts electrons. (webexhibits.org)
  • With the electron replacing the ejected fluoride ion, there are now equal numbers of positive and negative charges in the crystal, and the electron is held firmly in place by the surrounding positively charged calcium ions. (webexhibits.org)
  • Energetic ions are buried in the target's surface but its resistivity prevents neutralization by electrons from adjacent electrodes. (lesker.com)
  • In this study, damage formation processes by energetic ion bombardment have been simulated for Si/Ge/SiGe substrates by molecular dynamics (MD) simulations and dependence of ion induced damages on species of incident ions and their doses has been examined. (aps.org)
  • Vaudolon explained that the wall materials play a role in the plasma properties mainly through secondary electron emission, a phenomenon where high-energy ions hit the channel wall surface and induce the emission of secondary electrons. (sciencedaily.com)
  • Additionally, the erosion of the discharge cavity walls due to bombardment of high-energy ions shortens the thruster's lifetime. (sciencedaily.com)
  • Researchers have unexpectedly discovered that ions conduct faster than electrons in conjugated polymers. (materialstoday.com)
  • In this work we investigate how He + and Ne + bombardment influences roughness formation and preferential sputtering for polymer samples and how they compare to Ar + primary ions used in classical SIMS by combining experimental techniques with Molecular Dynamics (MD) simulations and SD_TRIM_SP modelling. (beilstein-journals.org)
  • Some of the same electrons stripped from sulfur and oxygen atoms during an earlier eruption return to strike atoms shot out by later blasts. (universetoday.com)
  • Because the energy levels of electron orbitals for the atoms of a given element are intrinsic, the fluorescent x-rays also have characteristic energies. (ou.edu)
  • A novel approach to incorporate cobalt atoms into a magnetite single crystal is demonstrated by a combination of x-ray spectro-microscopy, low-energy electron diffraction, and density-functional theory calculations. (aip.org)
  • Ion fluence dependence of the Si sputtering yield by noble gas ion bombardment. (mpg.de)
  • Sputtering and ion-induced electron emission of graphite under high-dose nitrogen bombardment. (mpg.de)
  • Sputtering of titanium by ion bombardment. (thermionics.com)
  • For He + bombardment, it is more of an issue for low keV impact energies and for the heavier primary ion species the preferential sputtering is sample dependent. (beilstein-journals.org)
  • Hence, preferential sputtering needs to be taken into account when interpreting images recorded under He + or Ne + bombardment on the HIM. (beilstein-journals.org)
  • The average power of the electron-resonance magnetron is limited by the amount of cathode emission, and the peak power is limited by the maximum voltage rating of the tube components. (rfcafe.com)
  • Secondary emission at the plate, caused by bombardment of the plate by electrons from the cathode, causes the dip in characteristics in that region. (vias.org)
  • Increase in plate voltage in the unstable region causes greater secondary emission, and therefore less net plate current, because one electron striking the plate may release more than one electron from it. (vias.org)
  • In the conventional Hall thruster configuration, the magnetized discharge is confined to an annular dielectric cavity with the anode at one end, where the gas is injected, and an external cathode injecting electrons. (sciencedaily.com)
  • Magnetic fields are used to trap hot electrons injected from the external cathode and prevent them from reaching the anode," Vaudolon said. (sciencedaily.com)
  • The output of a magnetron is reduced by the bombardment of the filament by electrons which travel in loops, shown in figure 2-22, views (B) and (C). This action causes an increase of filament temperature under conditions of a strong magnetic field and high plate voltage and sometimes results in unstable operation of the tube. (rfcafe.com)
  • The events that combine to enable pumping of gases under vacuum are: Entrapment of electrons in orbit by a magnetic field. (thermionics.com)
  • Once aloft, electrons whipped around by Jupiter's powerful magnetic field strike the neutral gases and ionize them (strips off their electrons). (universetoday.com)
  • The propellant gas, typically xenon, is ionized by electrons trapped in the magnetic field. (sciencedaily.com)
  • Basically an electron travels along the magnetic field line. (sciencedaily.com)
  • Three common types of anode blocks used in electron-resonance magnetrons are shown in figure 2-27. (rfcafe.com)
  • Figure 2-29A, shows the physical relationships of the resonant cavities contained in the hole-and-slot anode (figure 2-27, view (A)). This will be used when analyzing the operation of the electron-resonance magnetron. (rfcafe.com)
  • These chemical analyses are realized by means of electron microprobe techniques which allow accurate analyses on diverse objects from small single crystals suitable for X-ray diffraction experiments up to multiphase materials in phase diagram studies. (mpg.de)
  • The bright areas in the substrate located directly at the interface of the substrate and the epi layer represent holes in the TEM sample caused by the electron irradiation of the transmission electron microscope. (springer.com)
  • Such changes have brought renewed interest in physical damages caused by ion bombardment because, in typical gate etching processes of 3D devices, the channel surfaces are exposed directly to the ion irradiation from the plasma. (aps.org)
  • This permits the selection of single locations for irradiation at a constant electron flux over time. (ou.edu)
  • The electron microprobe, more formally called the Electron Probe Micro Analyzer (EPMA), is based upon the electron optical column of a conventional Scanning Electron Microscope (SEM), but incorporates a hardware addition specifically designed for the accurate, quantitative chemical analysis of solid materials. (ou.edu)
  • Coincidence spectroscopy: photoelectron-photoion-photoion coincidences (PEPIPICO), zero electron kinetic energy (ZEKE) spectroscopy, threshold electron spectroscopy. (infim.ro)
  • Results The implants Titamax® and External Hex (Titanium Fix, São José dos Campos, Brazil) exhibited characteristics of roughness through the blasting of particles, and OSSEOTITE®, Revolution® Implant (Sin, São Paulo, Brazil) and porous Master® (Connection System Prostheses, Aruja, Brazil) had porous characteristics analyzed by a scanning electron microscope (SEM) and energy dispersive spectroscopy (EDS). (bvsalud.org)
  • A negative ion may be missing from the structure, creating a site that will attract and trap any free electron. (webexhibits.org)
  • Ionizing radiation may come from high-energy photons that can be the product of natural decay of radioactive material, such as gamma rays, or the product of artificial bombardment of electrons onto Tungsten, such as x-rays. (medscape.com)
  • 28. The Pure Electron Discharge and its Applications in Radio Telegraphy and Telephony. (plasma-universe.com)
  • The epitaxial relationship and the microstructure of the GaN films are investigated by transmission electron microscopy (TEM). (springer.com)
  • In particular SEMPA was used to examine the rotation of the magnetization within domain walls and to study changes in magnetic microstructure due to Ar ion bombardment and annealing. (nist.gov)
  • The energy delivered to the tissues is measured in electron volts. (medscape.com)
  • Computer simulation of chemical erosion of graphite due to hydrogen ion bombardment. (mpg.de)
  • Electrons extracted from a glowing filament may be used to ionize gases. (britannica.com)
  • It can be shown by simple considerations that this type of nuclear reaction may be described in an essentially classical way like the fission of a liquid drop, and that the fission products must fly apart with kinetic energies of the order of hundred million electron-volts each. (todayinsci.com)
  • The effects of filament bombardment can be reduced by operating the filament at a reduced voltage. (rfcafe.com)
  • In some cases, the plate voltage and field strength are also reduced to prevent destructive filament bombardment. (rfcafe.com)
  • Adding antioxidants can push the resolution limit of polymer electron microscopy to reveal structures at smaller scales (blue) than could previously be observed (pink) in this false-color image. (materialstoday.com)
  • For the electrically conductive polymer examined in this study, this meant the researchers could follow the direction along which electrons travel. (materialstoday.com)
  • We have found that controlled Ar ion bombardment enhances the degradation of a-Si:H based surface passivation of c-Si surfaces. (tudelft.nl)
  • The RF's reversal of electrode polarity or the negative surface bias present during the pulsed DC's 'off' period, causes the highly mobile electrons from the plasma to quickly flood and neutralize the surface. (lesker.com)
  • In addition, availability of the secondary electron imaging mode used in conventional SEMs provides topographic (surface morphology) characterization for such applications as phase discrimination, surface reaction mechanisms, and component failure analysis. (ou.edu)
  • When an input event strikes the surface of the cone secondary electrons are created. (sisweb.com)
  • These electrons should travel down the channel and strike the emissive surface creating more electrons. (sisweb.com)
  • For negative ion detection, a positive ion is produced from the surface and detected by the electron multiplier. (sisweb.com)
  • Polarisation contrast and surface sensitive investigations in the scanning electron microscope necessitate often to adapt the standard preparation route to the concrete material and its mechanical properties. (mpg.de)
  • The samples were analyzed using a JEOL 3010 TEM as well as a FEI Tecnai F20 TEM, each operated with an electron acceleration voltage of 200 kV. (springer.com)
  • Each electron multiplier is delivered with a quality control label indicating its model number, test voltage, bias current at the test voltage and the date of shipment. (sisweb.com)
  • The secondary electrons will then be created deep enough in the voltage gradient that they will travel down the channel. (sisweb.com)
  • but, when a screen grid is added and its potential is higher than that of the plate, those electrons are drawn to the screen and produce a current in it. (vias.org)
  • Size comparisons of electron tubes and semiconductors. (rfcafe.com)
  • The grid acts as a barrier between any outside potentials that may attract the secondary electrons. (sisweb.com)
  • Possible mechanisms for the ion induced generation of electron-hole pairs are discussed. (tudelft.nl)
  • Based on the simulations results, damage formation mechanisms will be discussed and a semi-analytical model to predict the damage extent formed by ion bombardment will be also presented. (aps.org)
  • As a consequence, electrons and holes are spatially separated in such structures, leading to a reduced wave function overlap and a decreased radiative transition energy. (springer.com)
  • This result suggests that the ion flux determines the generation rate of electron-hole pairs in a-Si:H films, by which metastable defects are created at the H/a-Si:c-Si interface. (tudelft.nl)
  • The non-linearity in the unstable region disappears when the plate potential is made equal to or greater than the screen potential, because the secondary electrons remain at the plate. (vias.org)
  • The electron-resonance magnetron is the most widely used for microwave frequencies because it has reasonably high efficiency and relatively high output. (rfcafe.com)
  • The thin-film vacuum-deposition process combines physical-vapor deposition with ion bombardment. (anl.gov)
  • This force generation runs against the need for constant electron bombardment within the engine to produce plasma, meaning a consistent source of electricity is needed. (nationalinterest.org)
  • A free electron has moved into the gap and been trapped there, creating a color center we see as purple. (webexhibits.org)
  • to make a target of (an object, person, city, etc.) for attack or bombardment. (dictionary.com)
  • The target charge acts as a electrical barrier preventing further ion bombardment. (lesker.com)
  • Polymers can only be imaged to a certain point with high-resolution transmission electron microscopy (HRTEM), because the bombardment of electrons used to form images breaks the sample apart. (materialstoday.com)
  • 40007-98020 The manufacturing process of electron multipliers utilizes a number of glass forming and wet chemistry techniques. (sisweb.com)
  • Such sources are found with many electrode configurations, including electron-emitting filaments, and operate with wide ranges of pressures and voltages. (britannica.com)
  • Since LGO is very sensitive to electron bombardment, it is very difficult to obtain good quality high-resolution images of this material. (springer.com)
  • Large particles approximately 14 micrometers in diameter and not visible in secondary electron (SE) images were clearly identified within the lung tissue cells analyzed. (cdc.gov)
  • The electric field in the electron-resonance oscillator is a product of ac and dc fields. (rfcafe.com)
  • One development that has dominated solid-state technology, and probably has had a greater impact on the electronics industry than either the electron tube or transistor, is the INTEGRATED Circuit. (rfcafe.com)
  • The constants and operating conditions of the tube are such that the electron paths are somewhat different from those in figure 2-24. (rfcafe.com)
  • In the electron-resonance magnetron, the plate is constructed to resonate and function as a tank circuit. (rfcafe.com)
  • How does the Electron Microprobe work? (ou.edu)
  • Color centers fall into two categories: electron color centers and hole color centers. (webexhibits.org)
  • If the first strike electrons exit the cone then the detector will have poor collection efficiency. (sisweb.com)
  • 2. Explain the electron and the hole flow theory in semiconductors and how the semiconductor is affected by doping. (rfcafe.com)