US4169228A
Expired / Lapsed
US
⏱️ 0.0 years remaining
X-ray analyzer for testing layered structures
Assignee: International Business Machines Corp
•
Filing: 1978-06-05
•
Granted: 1979-09-25
•
Expires: 1998-06-05
Abstract
Abstract X-ray fluorescence produced by a primary X-ray beam incident at a very flat angle (below 1°) onto the surface of a specimen contained in a vacuum chamber is used to analyze shallow layers and/or to determine depths of shallow surface layers, such as a very thin (typically between about 10A and 10 3 A) silicon coating on Al or Cu layers which overlay a silicon substrate. Semiconductor profile determination may be another application of the invention.
Inventors
- 👤 Marian Briska
- 👤 Armin Bohg
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 18:16
CPC Classifications
G; G01; G01N; G01N23/00; G01N23/22; G01N23/223; G01N2223/00; G01N2223/07; G01N2223/076
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
114 words
An x-ray fluorescence analysis apparatus where highly parallelized x-rays are directable as primary beams under a predetermined angle onto a sample for exciting characteristic x-ray fluorescence beams which in turn are detectable by a beam detector for finding data on composition of elements of the respective excited layer thicknesses of the sample, comprising: means for directing a primary x-ray beam to penetrate a surface adjacent portion of said sample at an angle of incidence not exceeding 2°, the scattering radiation reflected from said sample, at an angle corresponding to said angle of incidence being suppressed; and x-ray spectrometer means for limiting detection to substantially only x-ray fluorescences, of said sample, excited by said beam.
Claim 2
Dependent Claim
114 words
An x-ray fluorescence analysis apparatus where highly parallelized x-rays are directable as primary beams under a predetermined angle onto a sample for exciting characteristic x-ray fluorescence beams which in turn are detectable by a beam detector for finding data on composition of elements of the respective excited layer thicknesses of the sample, comprising: means for directing a primary x-ray beam to penetrate a surface adjacent portion of said sample at an angle of incidence not exceeding 2°, the scattering radiation reflected from said sample, at an angle corresponding to said angle of incidence being suppressed; and x-ray spectrometer means for limiting detection to substantially only x-ray fluorescences, of said sample, excited by said beam.
Claim 3
Dependent Claim
13 words
Apparatus as claimed in claim 1 wherein said sample comprises a semiconductor wafers.
Claim 4
Dependent Claim
19 words
Apparatus as claimed in claim 1 characterized in that synchrotron radiation comprises a source of said primary x-ray beam.
Claim 5
Dependent Claim
22 words
Apparatus as claimed in claim 1 wherein said spectrometer comprises a crystal spectrometer for analyzing the X-ray fluorescence radiation of light elements.
Claim 6
Dependent Claim
18 words
Apparatus as claimed in claim 1 wherein said spectrometer includes a lithium-drifted silicon crystal for said beam detection.
Claim 7
Dependent Claim
19 words
Apparatus as claimed in claim 5 characterized in that synchrotron radiation comprises a source of said primary x-ray beam.
Claim 8
Dependent Claim
59 words
Apparatus as claimed in claim 1 wherein said sample is disposed in a vacuum chamber and said spectrometer means includes an energy dispersive wide angle radiation detector mounted at an end of an optical column in said chamber with said column extending through a wall of said chamber and externally thereof into a Dewar vessel filled with liquified gas.
Claim 9
Dependent Claim
18 words
Apparatus as claimed in claim 7 characterized in that synchrotron radiation comprises a source of primary x-ray beam.
Claim 10
Dependent Claim
15 words
Apparatus as claimed in claim 7 including a collimator for parallelizing said primary x-ray beam.
Claim 11
Dependent Claim
18 words
Apparatus as claimed in claim 9 wherein said spectrometer includes a lithium-drifted silicon crystal as a beam detector.
Claim 12
Dependent Claim
20 words
Apparatus as claimed in claim 10 characterized in that a synchrotron radiation comprises a source of said primary x-ray beam.
References Cited (Backward Citations)
US3525863A
Cited
US3663812A
Cited
US3765773A
Cited
US3839635A
Cited
US3963922A
Cited
US4028547A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1982-09-24 | 1983-03-26 | 1983-09-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1986-09-24 | 1987-03-26 | 1987-09-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1990-09-24 | 1991-03-26 | 1991-09-25 | $7700.00 | Window Closed / Lapsed |