US3109932A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Measurement of impurity concentration in semiconducting material
Assignee: AT&T Inc
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Filing: 1960-10-07
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Granted: 1963-11-05
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Expires: 1980-10-07
Abstract
No abstract record available.
Inventors
- 👤 William G Spitzer
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 21:15
CPC Classifications
G; G01; G01N; G01N21/00; G01N21/84; G01N21/88; G01R; G01R31/00; G01R31/28; G01R31/302; G01R31/308; H; H10; H10D; H10D62/00; H10D62/60; H10P; H10P74/00; H10P95/00
Claims Analysis
Total Claims: 1
Claim 1
Independent Claim
73 words
THE METHOD FOR DETERMINING THE PROFILE OF THE CONCENTRATION OF THE PREDOMINANT CONDUCTIVITY-TYPE DETERMINING IMPURITY IN A SEMICONDUCTIVE INGOT COMPRISING THE STEPS OF MEASURING THE REFLECTIVITY OF EACH OF A SUCCESSION OF ZONES OF SAID INGOT TO INFRARED RADIATION AT A PLURALITY OF DIFFERENT INFRARED WAVELENGTHS FOR LOCATING THE WAVELENGTH AT WHICH THE REFLECTIVITY IS A MINIMUM, AND CONVERTING SAID WAVELENGTH OF MINIMUM REFLECTIVITY THUS OBTAINED INTO A VALUE OF IMPURITY CONCENTRATION BY
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1966-11-04 | 1967-05-06 | 1967-11-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1970-11-04 | 1971-05-06 | 1971-11-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1974-11-04 | 1975-05-06 | 1975-11-05 | $7700.00 | Window Closed / Lapsed |