GB2426120A - A reflectron for use in a three-dimensional atom probe - Google Patents

A reflectron for use in a three-dimensional atom probe Download PDF

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Publication number
GB2426120A
GB2426120A GB0509638A GB0509638A GB2426120A GB 2426120 A GB2426120 A GB 2426120A GB 0509638 A GB0509638 A GB 0509638A GB 0509638 A GB0509638 A GB 0509638A GB 2426120 A GB2426120 A GB 2426120A
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United Kingdom
Prior art keywords
reflectron
electrode
curvature
front electrode
atom probe
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Withdrawn
Application number
GB0509638A
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GB0509638D0 (en
Inventor
Peter Panayi
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Imago Scientific Instruments Corp
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Polaron PLC
Imago Scientific Instruments Corp
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Publication date
Application filed by Polaron PLC, Imago Scientific Instruments Corp filed Critical Polaron PLC
Priority to GB0509638A priority Critical patent/GB2426120A/en
Publication of GB0509638D0 publication Critical patent/GB0509638D0/en
Priority to PCT/GB2006/001694 priority patent/WO2006120428A2/en
Priority to CNA2006800157105A priority patent/CN101176185A/en
Priority to JP2008510634A priority patent/JP2009507328A/en
Priority to EP06727056.1A priority patent/EP1880406B1/en
Publication of GB2426120A publication Critical patent/GB2426120A/en
Priority to US12/425,291 priority patent/US8134119B2/en
Withdrawn legal-status Critical Current

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    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J37/00—Discharge tubes with provision for introducing objects or material to be exposed to the discharge, e.g. for the purpose of examination or processing thereof
    • H01J37/02—Details
    • H01J37/04—Arrangements of electrodes and associated parts for generating or controlling the discharge, e.g. electron-optical arrangement or ion-optical arrangement
    • H01J37/05—Electron or ion-optical arrangements for separating electrons or ions according to their energy or mass
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B82—NANOTECHNOLOGY
    • B82Y—SPECIFIC USES OR APPLICATIONS OF NANOSTRUCTURES; MEASUREMENT OR ANALYSIS OF NANOSTRUCTURES; MANUFACTURE OR TREATMENT OF NANOSTRUCTURES
    • B82Y15/00—Nanotechnology for interacting, sensing or actuating, e.g. quantum dots as markers in protein assays or molecular motors
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J49/00—Particle spectrometers or separator tubes
    • H01J49/26—Mass spectrometers or separator tubes
    • H01J49/34—Dynamic spectrometers
    • H01J49/40—Time-of-flight spectrometers
    • H01J49/405—Time-of-flight spectrometers characterised by the reflectron, e.g. curved field, electrode shapes
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J2237/00—Discharge tubes exposing object to beam, e.g. for analysis treatment, etching, imaging
    • H01J2237/05—Arrangements for energy or mass analysis
    • H01J2237/053—Arrangements for energy or mass analysis electrostatic
    • H01J2237/0535—Mirror analyser

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  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Nanotechnology (AREA)
  • Analytical Chemistry (AREA)
  • Health & Medical Sciences (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • General Health & Medical Sciences (AREA)
  • Molecular Biology (AREA)
  • Crystallography & Structural Chemistry (AREA)
  • Other Investigation Or Analysis Of Materials By Electrical Means (AREA)

Abstract

A reflectron for reflecting ions from a sample under investigation in a 3D atom probe, the reflectron having improved space-angle focussing over a wide range of entry angles (up to 45{) and configured to substantially eliminate chromatic aberration. The reflectron comprises a front electrode 2, a back electrode 3, and a plurality of intermediate electrodes 4, at least one of the front and back electrodes being capable of generating a curved electric field substantially equivalent to the electric field produced by a point charge. Preferably the front and/or back electrodes have concave surfaces facing the ion source, the concave surfaces having a constant radius of curvature equal to the distance between the respective electrodes and the ion source.

Description

REFLECTRON
The present invention relates to a reflectron for a three-dimensional atom probe.
Three-dimensional atom probes may incorporate a reflectron. The reflectron effectively acts as a mirror', and reverses the direction of an ion which is being analysed in the mass spectrometer. The ion is reflected from its initial direction from an ion source onto a detector. The reflectron can increase the mass resolution of the three- dimensional atom probe in a similar way to its use in a time-of-flight mass spectrometer.
A conventional reflectron is formed of a series of ring electrodes, which define a hollow cylinder. The electrodes are each held at an electric potential, the potential increasing in a direction of travel of an ion from an ion source. The electrodes generate a uniform field over the cross-section of the reflectron. The ions travel in a parabola through the reflectron. The reflectron can be configured such that the time taken by the ion to travel through the atom probe is substantially independent of the initial energy of the ion. This is known as time focussing.
The ion source in a three-dimensional atom probe is a specimen under examination with a curved surface of small dimensions. The ions originate from a small area of the surface and proceed towards a detector plate at some distance away. They thus form an image on the detector of the sample area at a very large magnification. A conventional reflectron used in an atom probe has the disadvantage that an angle spread of more than approximately 8 degrees results in an excessively large reflectron and detector or alternatively an excessively short flight path.
A conventional reflectron used in an atom probe has the disadvantage that wide angle spreads introduce a chromatic aberration. Chromatic aberration is an error in the position of the detected ion dependent on the energy of the ion.
A reflectron used in a three-dimensional atom probe must accept ions over a significantly larger range of angles than a reflectron in a time-offlight mass spectrometer. A reflectron designed for use in an atom probe or a time-of- flight mass spectrometer will not suitable for use in a three-dimensional atom if they will only accept and reflect ions incident over a small range of angles.
The present invention aims to address at least some of the problems associated with the prior art. Accordingly, the present invention provides a reflectron for reflecting an ion from an ion source in a threedimensional atom probe, the reflectron comprising: a front electrode; and a back electrode; wherein at least one of the front and back electrodes
is capable of generating a curved electric field;
the front electrode and back electrode configured such that when an electric potential is applied to at least one
of the electrodes an electric field is generated
substantially equivalent to an electric field produced by a point charge, such that an ion incident on the reflectron is reflected.
The reflectron according to the present invention has improved space angle focusing of the ions over a wide range of angles. The reflectron of the present invention may also be configured to reduce or almost eliminate chromatic aberration.
The front electrode preferably has a concave surface facing the ion source. Advantageously, the concave surface of the front electrode is curved with a constant radius of curvature.
The front electrode may take any suitable form but will typically comprises a mesh.
The front electrode is preferably held at ground potential.
The front electrode is preferably held at a potential of at least approximately 1.08 times an equivalent energy of an ion to be reflected.
The back electrode preferably has a concave surface facing the ion source. Advantageously, the concave surface of the back electrode is preferably curved with a constant radius of curvature.
The back electrode may take any suitable form but will typically comprises a plate.
Preferably, when the reflectron is incorporated in a three-dimensional atom probe, the radius of curvature of the front electrode is substantially equal to a distance between the front electrode and a detector for detecting ions in the three-dimensional atom probe. The radius of curvature of the back electrode is preferably substantially equal to a distance between the back electrode and the detector for detecting ions in the three-dimensional atom probe.
Preferably, a radius of curvature of the front electrode and a radius of curvature of the back electrode are such that the two electrodes are concentric.
The reflectron preferably also contains a plurality of intermediate electrodes disposed between the front electrode and the back electrode. Each of the intermediate electrodes is preferably formed as an annulus.
Each of the intermediate electrodes is preferably held at an electric potential equivalent to the potential at their location which would be generated by the point charge simulated by the front electrode and back electrode.
The present invention also provided a three-dimensional atom probe incorporating a reflectron as herein described.
In this case, the front electrode preferably has a concave surface having a constant radius of curvature, the radius of curvature of the front electrode being substantially equal to a distance between the front electrode and a detector for detecting ions in the three-dimensional atom probe.
Advantageously, the back electrode has a concave surface having a constant radius of curvature, the radius of curvature of the back electrode being substantially equal to a distance between the back electrode and a detector for detecting ions in the three-dimensional atom probe.
A preferred embodiment of the present invention will now be described, by way of example only, with reference to the accompanying Figures, in which: Figure 1 is a plan view of the reflectron of the present invention showing lines of equal electric potential.
Figure 2 is a plan view of the reflectron of the present invention showing example paths of ions.
Figure 3 is a plan view of the reflectron of the present invention showing an example path of an ion.
Figure 4 is a plan view of the reflectron of the present invention showing paths of ions with different initial ion trajectories.
Figure 5 is a plan view of the reflectron of the present invention showing paths of ions with different initial energy energies.
A reflectron may be incorporated as part of a three- dimensional atom probe. A three-dimensional atom probe removes individual atoms from the surface of a needle shaped specimen with a small tip radius. The atom becomes an ion and is accelerated towards a detector plate which is as large as possible, and detects a position of the ion which corresponds with the position of the atom on the specimen surface. The detector electronics measures the position at which the ion hits the plate and also measures the mass/charge ratio of the resulting ion by timing the flight of the ion through the three dimensional atom probe.
The reflectron substantially reverses the direction of the ions, by generating an electric potential greater than the energy equivalent of the ion. An ion generally enters the reflectron at an angle to a radius line of the electrodes, so that the ion travels in an ellipse through the reflectron. The detector is offset from a path of the ions from their source to the reflectron. In the limiting case of the conventional planar reflectron, the radius becomes the longitudinal axis of the reflectron and the ellipse becomes a parabola.
The reflectron of the present invention is preferably configured such that the time taken to travel through the three-dimensional atom probe, including the time spent in the reflectron, is independent of the initial energy of the ion. This is known as time focussing, and improves the mass resolution of the spectrometer.
A three-dimensional atom probe is used for examining the structure of materials, particularly metals, at an atomic scale. A three-dimensional atom probe will incorporate timing means to measure the time taken for the ion to travel a predetermined distance within the three dimensional atom probe. The ion travels through an electric field, and this can be used to calculate the mass/charge ratio of the ion, and so determine its identity. Three- dimensional atom probes, and their relationship to atom probes generally, are disclosed in the publication Atom Probe Field Ion Microscopy' by M.K. Miller, A. Cerezo, M.G.
Hetherington and G.D.W. Smith, OUP 1996, which is incorporated herein.
The basic method of carrying out an analysis with a three-dimensional atom probe first involves obtaining a field ion image of the specimen. This is achieved with a field ion microscope incorporated in the threedimensional atom probe. The specimen is in the form of a fine wire or needle, having a sharp point. The specimen is located in a cryostat and cooled to a temperature of typically 20K to 100K. The field ion microscope is filled with an inert gas, such as helium or neon, to a pressure in the order of 1O3 Pa. A high voltage is applied to the specimen, typically kV.
Inert gas ions are emitted from the specimen and strike a microchannel plate, which generates secondary electrons.
The electrons are accelerated onto a fluorescent screen, generating an image of the specimen at an atomic scale.
This process is known as field ion microscopy, and allows part of the specimen to be selected.
In order to identify the atoms of the specimen, the three-dimensional atom probe functions as a mass spectrometer. The inert gas is eliminated or reduced in pressure. The fluorescent screen is replaced by an electronic detector which measures both the position of the ion and their time of arrival in the same manner as a time of flight mass spectrometer. This change of configuration may be achieved by reorienting the specimen to point towards the alternative detector or reflectron. The surface atoms are field evaporated by, for example, applying short pulses of higher voltage to the specimen.
In a three-dimensional atom probe, ions from the specimen sample are emitted from an area of the tip which depends on the curvature. They are emitted approximately radially to the tip curvature. A detector is located typically 100 to 600 mm from the tip. The detector is typically square or circular, and has a width in the order of 40 to 100 mm.
There is an image area on the tip of the specimen from which ions emitted from the specimen will strike the detector. The ratio of the linear dimensions of the detector and image area on the specimen is termed the magnification.
The magnification is typically too large for optimum analysis of the specimen so it needs to be reduced. The magnification can be reduced by reducing the detector distance; by increasing the tip radius or by increasing the detector size. For technical reasons, the detector is limited in size; the tip radius is limited to between 50 and nm, and the detector distance needs to be as large as possible. Thus, the best way to achieve a magnification decrease is to accept a fairly wide cone angle of emitted ions from the tip. This means however that a reflectron must function with a wide range of input angles. Typically degrees or more would be desirable. For a conventional planar reflectron however the performance degrades both in mass resolution terms and from the point of view of chromatic aberration if the cone angle is much greater than degrees. This also means that the detector distance With reference to Figures 1 and 2, a reflectron 1 according to the present invention comprises a curved front electrode 2. The front electrode 2 is formed in the shape of part of a sphere, such that it has a constant radius of curvature. The front electrode 2 has a concave side 6 and a convex side 7, and has a diameter of approximately 80 mm to 200 ram. The front electrode 2 is comprised of a fine mesh or grid. The mesh allows approximately 90% of incident ions to pass through.
A plurality of annular electrodes 4 are arranged behind the front electrode 2, on the convex side 7 of the front electrode 2. The annular electrodes 4 do not incorporate a mesh, but are ring shaped with a central circular aperture through which the ions can freely pass. The number of these electrodes, their spacing and the voltages on them can vary with the specific design.
A back electrode 3 is located at the opposite end of the reflectron 1 from the front electrode 2. The back electrode 3 is spaced apart from the front electrode 2 by typically 40 to 100 mm. This distance depends on many factors according to the magnification and time focussing requirements. The annular electrodes 4 are thus intermediate the front electrode 2 and back electrode 3.
The back electrode 3 is aligned along a longitudinal axis of the reflectron 1 with the front electrode 2 and annular electrodes 4. The back electrode 3 has an upper surface 5 which is curved in the shape of part of a sphere.
The upper surface 5 of the back electrode 3 is preferably concentric with the front electrode 2 and thus has a constant radius of curvature which is greater than the radius of curvature of the front electrode 2. The upper 10 - surface 5 is concave, the concave surface 5 facing towards the front electrode 2.
The reflectron 1 is suitable for use in a three- dimensional atom probe as previously described. With reference to Figure 2, the concave side 6 of the front.
electrode 2 and the concave upper side 5 of the back electrode 3 are orientated approximately towards an ion source 10.
The radius of curvature of the front electrode 2 is preferably equal to or smaller than the radius of curvature of the back electrode 3.
For example, the radius of curvature of the front electrode 2 may be approximately the same as the distance between a detector and the front electrode 2. The radius of curvature of the upper surface 5 of the back electrode 3 may be substantially the same as the distance between the detector and the back electrode 3. The front electrode 2 and the upper surface 5 are each shaped as a part of spheres which may have their centres in proximity to the detector.
This arrangement allows the reflectron 1 to spatially focus the ions onto the detector.
With reference to Figure 3, the reflectron 1 achieves spatial focussing of the ions onto a detector when an entry angle qi is up to approximately 450* The reflectron 1 is able to reduce the magnification of the threedimensional atom probe such that the image on the detector corresponds to a much larger area of the sample. The point 12 is the - 11 - centre of the spheres of the electrodes 2,3, and the focus of the elliptical path followed by the ions.
Figure 4 is a plan view of the reflectron of the present invention showing the different ion trajectory geometries. Within the reflectron 1, the ion follows an elliptical path. A focus of the ellipse is at the centre of curvature of the electrodes. Analytic expressions exist for the major and minor diameters of the ellipse, and the other angles shown for given reflectron parameters and for each angle that the incident ion path makes with a datum line between the specimen tip and the centre of curvature. Figure 4 shows the position of the detector 11.
The reflectron 1 achieves almost linear space angle focusing of the ions over a wide range of angles, and so is able to reduce the magnification of the three dimensional atom probe such that the image on the detector corresponds to a much larger area of the sample. The relationship between the angle at which an ion is emitted from the ion source 10, and the position on the detector 11 is linear.
This means that the image produced by the detector 11 corresponds to the sample without distortion.
The trajectories in all the figures are calculated from analytic expressions. Analytic expressions are also available for the time the ion spends in the reflectron and the derivative of the time with ion energy. The latter is used to determine the reflectron parameters used to calculate the above trajectories.
- 12 - Figure 5 shows example paths of ions emitted at the same angle from the specimen with a range of initial energies. The ions shown have an exaggerated energy variation in the range of +/- 10%. Typically, an energy variation in the range +/- 1% would be expected.
The ability of the reflectron 1 to focus ions of different energies onto substantially the same position on the detector reduces chromatic aberration. When the centre of the spheres defined by the front electrode and back electrode are in the same plane as the detector, chromatic aberration can be substantially eliminated.
The reduction in chromatic aberration is possible because the lateral shift in exit position of the ion due to an energy change can be compensated for by the change in exit angle caused by the same energy variation. This occurs when the centre of curvature of the electrodes is near to the position of the detector. With reference to Figure 3, the entry angle is the same as exit angle c, which indicates that the position of the ion on the detector is not substantially dependent on the energy of the ion.
The reflectron 1 can accept ions diverging over a relatively large angle. The angle for which the reflectron 1 can perform time focussing and substantially linear spatial focussing of ions with substantially eliminated chromatic aberration is approximately three times greater than for a conventional uniform field reflectron. The reflectron 1 may be smaller than a conventional uniform field reflection of the same diameter and for the same external flight distance and still achieve time focussing.
- 13 - In use, an electric potential is applied to the front electrode 2, back electrode 3 and annular electrodes 4. The potential applied to the back plate 3 is greater than the equivalent energy of the ions which are to be measured.
This ensures that the ions are reflected back towards the source of the ions before they reach the back electrode 3.
The potentials applied to all the electrodes are calculated to ensure that the field within the reflectron is always directed radially away from the centre of curvature.
The annular electrodes maintain the correct potentials to minimise the edge effect caused by the fact that the front and back electrodes are only partial spheres.
The intermediate, annular electrodes 4 are spaced and held at appropriate voltages to ensure that the field inside the reflectron is as closely as possible equivalent to that which would be generated by a theoretical point charge of suitable value located at the centre of curvature. The annular electrodes 4 are each held at the potential which would be present at their location due to the point charge which the reflection 1 aims to simulate.
The equipotentja field lines 13 are curved and
substantially in the shape of part of a sphere. The field generated by the reflectron 1 approximately mimics the field which would be generated by a point charge located at the centre of the spheres defined by the front and back electrodes. The centre of the spheres defined by the front and back electrodes is preferably in proximity to the detector. The centre of the spheres defined by the front - 14 and back electrodes may be at approximately the same distance from the electrodes 2,3 as the detector is from the respective electrodes 2,3. The centre of the spheres defined by the front and back electrodes preferably will not coincide with the detector, if the detector is offset from the axis of the electrodes 2,3. Since the reflectron 1 substantially simulates a point charge, ions in the reflectron move in an ellipse.
An ion from the ion source 10 first passes through the mesh of the front electrode 2. The path of the ion is altered by the non-uniform electric potential it experiences. The ion passes through the central aperture of at least some of the annular electrodes 4. The electric potential the ion continues to experience within the reflectron 1 causes its speed in the direction of an axis of its elliptical orbit to reduce to zero, before the ion reaches the back plate 3. The electric potential applied to the back plate 3, annular rings 4 and front electrode 2 causes the ion to accelerate back towards the front electrode 2 and away from the back plate 3. The ion then passes back through the annular electrodes 4 and front electrode 2 and continues until it hits the detector.
The time taken by the ion to travel from a point adjacent the ion source to the detector is calculated, and used to calculate the mass/charge ratio of the ion. The identity of the ion is determined by reference to known values for the mass/charge ratio of ions.
Typically the mesh is at ground potential and the back electrode is held at a potential equal to typically 1.08 - 15 - times the nominal energy of the ions. The annular electrodes are held at intermediate potentials between the potential of the front electrode 2 and back electrode 3.
The potential of the annular electrodes 4 increases towards the back electrode 4. The potentials of the annular electrodes 4 are calculated to maintain a substantially radial field at the edges of the reflectron 1. The annular electrodes thus compensate for the front and back electrodes 2,3 forming only part of a sphere, and not a complete sphere.
The front electrode is described as a mesh or grid.
Alternatively, it may be formed from a solid material with holes or may be replaced by an electrostatic lens arrangement consisting of further annular electrodes held at different voltages.
The back electrode is described as spherically curved, however, the back electrode could also have a different type of curvature or be planar. The curvature of the front electrode could also not be constant. The shape of the front electrode has a greater effect on an ion trajectory than the back electrode, and so a planar back electrode could be utilised. Alternatively, a planar front electrode could be used with a curved back electrode. The front electrode and back electrode are therefore not necessarily concentric.
The centres of the spheres defined by the front electrodes and back electrodes has been described as being adjacent to or in proximity to the detector. Alternatively, the centre of the spheres defined by the front electrodes - 16 - and back electrodes may be located away from the detector.
Thus, the radius of curvature of the front electrode and/or the rear electrode does not necessarily substantially equal the distance from that electrode to the detector.

Claims (19)

  1. - 17 - Claims: 1. A reflectron for reflecting an ion from an ion source in
    a three- dimensional atom probe, comprising: a front electrode; and a back electrode; wherein at least one of the front and back electrodes
    is capable of generating a curved electric field;
    the front electrode and back electrode configured such that when an electric potential is applied to at least one
    of the electrodes an electric field is generated
    substantially equivalent to an electric field produced by a point charge, such that an ion incident on the reflectron is reflected.
  2. 2. The reflectron of claim 1 wherein the front electrode has a concave surface facing the ion source.
  3. 3. The reflectron of claim 1 or 2 wherein the back electrode has a concave surface facing the ion source.
  4. 4. The reflectron of any one of the preceding claims wherein a concave surface of the front electrode is curved with a constant radius of curvature.
  5. 5. The reflectron of any one of the preceding claims wherein a concave surface of the back electrode is curved with a constant radius of curvature.
  6. 6. The reflectron of any one of the preceding claims wherein, in use, when incorporated in a three-dimensional atom probe, the radius of curvature of the front electrode - 18 - is substantially equal to a distance between the front electrode and a detector for detecting ions in the threedimensional atom probe.
  7. 7. The reflectron of any one of the preceding claims wherein, in use, when incorporated in a three-dimensional atom probe, the radius of curvature of the back electrode is substantially equal to a distance between the back electrode and a detector for detecting ions in the three- dimensional atom probe.
  8. 8. The reflectron of any one of the preceding claims wherein a radius of curvature of the front electrode and a radius of curvature of the back electrode are such that the two electrodes are concentric.
  9. 9. The reflectron of any one of the preceding claims wherein a plurality of intermediate electrodes are disposed between the front electrode and the back electrode.
  10. 10. The reflectron of claim 9 wherein each of the intermediate electrodes are held at an electric potential equivalent to the potential at their location which would be generated by the point charge simulated by the front electrode and back electrode.
  11. 11. The reflectron of claims 9 or 10 wherein each of the intermediate electrodes are formed as an annulus.
  12. 12. The reflectron of any one of the preceding claims wherein the front electrode is held at ground potential.
    - 19 -
  13. 13. The reflectron of any one of the preceding claims wherein the front/back electrode is held at a potential of approximately 1.08 times an equivalent energy of an ion to be reflected.
  14. 14. The reflectron of any one of the preceding claims wherein the front electrode comprises a mesh.
  15. 15. The reflectron of any one of the preceding claims wherein the back electrode comprises a plate.
  16. 16. A three-dimensional atom probe comprising a reflectron as defined in any one of the preceding claims.
  17. 17. A three-dimensional atom probe comprising a reflectron as defined in claim 1, wherein: the front electrode has a concave surface having a constant radius of curvature; and the radius of curvature of the front electrode is substantially equal to a distance between the front electrode and a detector for detecting ions in the three- dimensional atom probe.
  18. 18. The three-dimensional atom probe of claim 17 wherein: the back electrode has a concave surface having a constant radius of curvature; and the radius of curvature of the back electrode is substantially equal to a distance between the back electrode and a detector for detecting ions in the three-dimensional atom probe.
    - 20 -
  19. 19. A reflectron substantially as hereinbefore described with reference to and as shown in the accompanying drawings.
GB0509638A 2005-05-11 2005-05-11 A reflectron for use in a three-dimensional atom probe Withdrawn GB2426120A (en)

Priority Applications (6)

Application Number Priority Date Filing Date Title
GB0509638A GB2426120A (en) 2005-05-11 2005-05-11 A reflectron for use in a three-dimensional atom probe
PCT/GB2006/001694 WO2006120428A2 (en) 2005-05-11 2006-05-10 Reflectron
CNA2006800157105A CN101176185A (en) 2005-05-11 2006-05-10 Reflectron
JP2008510634A JP2009507328A (en) 2005-05-11 2006-05-10 Reflectron
EP06727056.1A EP1880406B1 (en) 2005-05-11 2006-05-10 Reflectron
US12/425,291 US8134119B2 (en) 2005-05-11 2009-04-16 Reflectron

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
GB0509638A GB2426120A (en) 2005-05-11 2005-05-11 A reflectron for use in a three-dimensional atom probe

Publications (2)

Publication Number Publication Date
GB0509638D0 GB0509638D0 (en) 2005-06-15
GB2426120A true GB2426120A (en) 2006-11-15

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Families Citing this family (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2013091019A1 (en) * 2011-12-22 2013-06-27 Bruker Biosciences Pty Ltd Improvements in or relating to mass spectrometry
EP2908329B1 (en) * 2012-10-10 2022-01-12 Shimadzu Corporation Time-of-flight mass spectrometer
CN104392888B (en) * 2014-10-17 2017-07-11 大连民族学院 A kind of compact ion reflector
CN106653559B (en) * 2016-11-18 2018-06-26 西北核技术研究所 A kind of time of-flight mass spectrometer with wide Voice segment reflector
JP2020145157A (en) * 2019-03-08 2020-09-10 キオクシア株式会社 Atom probe inspection device, field ion microscope, and strain correction method

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4731532A (en) * 1985-07-10 1988-03-15 Bruker Analytische Mestechnik Gmbh Time of flight mass spectrometer using an ion reflector
US5017780A (en) * 1989-09-20 1991-05-21 Roland Kutscher Ion reflector
GB2386750A (en) * 2001-11-17 2003-09-24 Bruker Daltonik Gmbh Space-angle focussing reflector for a time-of-flight mass spectrometer
EP1376650A1 (en) * 2001-03-26 2004-01-02 Kanazawa Institute of Technology Scanning atom probe and analysis method using scanning atom probe

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4731532A (en) * 1985-07-10 1988-03-15 Bruker Analytische Mestechnik Gmbh Time of flight mass spectrometer using an ion reflector
US5017780A (en) * 1989-09-20 1991-05-21 Roland Kutscher Ion reflector
EP1376650A1 (en) * 2001-03-26 2004-01-02 Kanazawa Institute of Technology Scanning atom probe and analysis method using scanning atom probe
GB2386750A (en) * 2001-11-17 2003-09-24 Bruker Daltonik Gmbh Space-angle focussing reflector for a time-of-flight mass spectrometer

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CN101176185A (en) 2008-05-07

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