US4810879A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Charged particle energy analyzer
Assignee: Kratos Analytical Ltd
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Filing: 1987-04-10
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Granted: 1989-03-07
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Expires: 2007-04-10
Abstract
Abstract A charged particle energy analyzer, such as a microscope or spectrometer, includes a magnetic immersion lens 10 to focus charged particles emitted from an irradiated specimen 5 located within the magnetic field of the lens. A collecting aperture 18 defines the area of the irradiated specimen from which charged particles can be brought to a focus in the image plane of the lens but an aperture 21 in this plane selects and defines a much smaller area of the specimen from which the received particles are passed to a suitable energy analyzing means 25. The energy analyzing means 25 then performs energy analysis of the small selected area of the specimen by imaging the small area with emitted particles of a predetermined energy, or energy scanning the particles emitted from this area, so giving a chemical analysis of the small selected area of the specimen surface.
Inventors
- 👤 Andrew R. Walker
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 05:31
CPC Classifications
H; H01; H01J; H01J37/00; H01J37/252; H01J37/26; H01J37/285; H01J49/00; H01J49/44; H01J49/46; H01J2237/00; H01J2237/05; H01J2237/053
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
186 words
A charged particle energy analyser for investigating a selected area of the surface of a specimen comprising a specimen holder, a source of radiation arranged to direct radiation on to an external surface of a specimen on the holder and to cause charged particles to be emitted therefrom, a magnetic lens which generates a magnetic imaging field, the lens being so disposed that the specimen holder lies within and on the axis of the magnetic imaging field of the lens and particles emitted from the specimen are brought to a focus by the field, a diaphragm containing a collection aperture disposed on the axis of the field to define the collection angle of the lens and analysing means for analysing the energy of the charged particles collected from the specimen and received by said analysing means, characterised by a further diaphragm containing an aperture on or adjacent to the axis of the lens and located between said collection aperture and the analysing means to define a restricted area of the specimen from which the particles are brought to a focus and supplied to said analysing means.
Claim 2
Dependent Claim
186 words
A charged particle energy analyser for investigating a selected area of the surface of a specimen comprising a specimen holder, a source of radiation arranged to direct radiation on to an external surface of a specimen on the holder and to cause charged particles to be emitted therefrom, a magnetic lens which generates a magnetic imaging field, the lens being so disposed that the specimen holder lies within and on the axis of the magnetic imaging field of the lens and particles emitted from the specimen are brought to a focus by the field, a diaphragm containing a collection aperture disposed on the axis of the field to define the collection angle of the lens and analysing means for analysing the energy of the charged particles collected from the specimen and received by said analysing means, characterised by a further diaphragm containing an aperture on or adjacent to the axis of the lens and located between said collection aperture and the analysing means to define a restricted area of the specimen from which the particles are brought to a focus and supplied to said analysing means.
Claim 3
Dependent Claim
26 words
A charged particle energy analyser according to claim 1 having means for changing the restricted area of the specimen from which the charged particles are received.
Claim 4
Dependent Claim
33 words
A charged particle analyser according to claim 2 wherein the means for changing the restricted area comprises means for deflecting the path of the charged particles relative to the axis of the analyser.
Claim 5
Dependent Claim
25 words
A charged particle energy analyser according to claim 1 having a magnifying lens located in the path of charged particles preceding the energy analysing means.
Claim 6
Dependent Claim
18 words
A charged particle energy analyser according to claim 1 wherein the magnetic lens is a snorkel type lens.
Claim 7
Dependent Claim
20 words
A charge particle energy analyzer according to claim 1 wherein the magnetic lens has asymmetric polepieces of substantially different diameters.
Claim 8
Dependent Claim
38 words
A charged particle energy analyzer according to claim 1 having means for changing the energy of the charged particles by simultaneously altering the strength of the magnetic imaging field of the lens and of the energy analyzing means.
Claim 9
Dependent Claim
31 words
A charge particle energy analyzer according to claim 1 having means for isolating the specimen holder from earth and electrostatically biasing it either positively or negatively with respect to earth potential.
Claim 10
Dependent Claim
41 words
A charged particle energy analyzer according to claim 1 having means for charge neutralizing an insulating specimen bombarded by a beam of particles selected from the group comprising electrons, ions, neutrals (selected from the group comprising atoms and molecules) and photons.
References Cited (Backward Citations)
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| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
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| 3.5 Years (Year 4) | 1992-03-06 | 1992-09-05 | 1993-03-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-03-06 | 1996-09-05 | 1997-03-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-03-06 | 2000-09-05 | 2001-03-07 | $7700.00 | Window Closed / Lapsed |