US3609352A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Secondary electron energy analyzing apparatus
Assignee: RCA Licensing Corp
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Filing: 1970-05-18
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Granted: 1971-09-28
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Expires: 1990-05-18
Abstract
Abstract A secondary electron energy analyzer employs a pair of spaced coaxial cylinders with entrance and exit slots in the inner cylinder, the distance between the slots and the potential between the cylinders being such that secondary electrons emitted from a specimen located at a point on the axis of the cylinders enter the space between the cylinders at the entrance slot and are focused at the exit slot. An electron multiplier is located within the inner cylinder to receive the focused electrons. The outer cylinder may be split into two portions, each with its individual slots and operated at slightly different potentials, so that electrons of different energies are focused at the two exit slots, measurement of the difference in the outputs from the two portions yielding the derivative of the energy distribution curve of secondary electrons.
Inventors
- 👤 Lawrence A Harris
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 02:28
CPC Classifications
H; H01; H01J; H01J49/00; H01J49/44; H01J49/46; H01J49/48; H01J49/482
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
211 words
Apparatus for analyzing the energies of secondary electrons comprising a pair of spaced coaxial conductive cylinders, a source of primary electrons located along the axis of said cylinders, means for supporting a specimen to be examined along said axis, the inner of said cylinders having longitudinally spaced entrance and exit slots, means supplying a fixed potential to said inner cylinder, means supplying an electron-deflecting potential to the outer of said cylinders, said entrance slot being spaced relative to said supporting means so that secondary electrons having energies within a range emitted from a specimen pass through said entrance slot to enter the region between said cylinders, the distance between said entrance and exit slots and the value of the electron-deflecting potential being such that electrons of a particular energy are focused at said exit slot, electron multiplier means within said inner cylinder and positioned to receive the focused electrons, current indicating means connected to said multiplier means, said outer cylinder comprising two substantially semicylindrical members insulated from each other, said exit slot comprising two circumferentially spaced openings in said inner cylinder and means supplying different deflecting potentials to said two semicylindrical members so that electrons of different energies are focused at said two openings and supplied to said electron multiplier means.
Claim 2
Dependent Claim
211 words
Apparatus for analyzing the energies of secondary electrons comprising a pair of spaced coaxial conductive cylinders, a source of primary electrons located along the axis of said cylinders, means for supporting a specimen to be examined along said axis, the inner of said cylinders having longitudinally spaced entrance and exit slots, means supplying a fixed potential to said inner cylinder, means supplying an electron-deflecting potential to the outer of said cylinders, said entrance slot being spaced relative to said supporting means so that secondary electrons having energies within a range emitted from a specimen pass through said entrance slot to enter the region between said cylinders, the distance between said entrance and exit slots and the value of the electron-deflecting potential being such that electrons of a particular energy are focused at said exit slot, electron multiplier means within said inner cylinder and positioned to receive the focused electrons, current indicating means connected to said multiplier means, said outer cylinder comprising two substantially semicylindrical members insulated from each other, said exit slot comprising two circumferentially spaced openings in said inner cylinder and means supplying different deflecting potentials to said two semicylindrical members so that electrons of different energies are focused at said two openings and supplied to said electron multiplier means.
Claim 3
Dependent Claim
34 words
The apparatus of claim 1 in which said electron multiplier means comprises a pair of electron multipliers positioned respectively to receive electrons from a different one of the two openings of said exit slot.
Claim 4
Dependent Claim
35 words
The apparatus of claim 2 in which said pair of electron multipliers are connected to a differential amplifier whereby the difference in output currents from the two openings of said exit slot can be measured.
Claim 5
Dependent Claim
37 words
The apparatus of claim 3 which includes means connected to said differential amplifier to compensate for differences in the gain through the pair of electron multipliers which means comprises a balance control connected across said differential amplifier.
Claim 6
Dependent Claim
32 words
The apparatus of claim 1 which includes means superimposing a time-varying electric potential on said deflecting potential whereby the rate of change of the energy distribution curve of electrons may be measured.
Claim 7
Dependent Claim
42 words
The apparatus of claim 5 in which said time-varying electric potential supplying means comprises a transformer having a secondary winding connected in series with the electron deflection potential means and means supplying an alternating current to the primary wInding of said transformer.
Claim 8
Dependent Claim
17 words
The apparatus of claim 1 in which the deflecting potential supply to said semicylindrical members is variable.
Claim 9
Dependent Claim
47 words
The apparatus of claim 1 in which secondary electrons are emitted in a substantially solid angle from a specimen being examined and said entrance slot is positioned along the inner cylinder so that it subtends an annular area which includes approximately 12 percent of such solid angle.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-09-27 | 1975-03-29 | 1975-09-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-09-27 | 1979-03-29 | 1979-09-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-09-27 | 1983-03-29 | 1983-09-28 | $7700.00 | Window Closed / Lapsed |