US3919639A
Expired / Lapsed
US
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Method for determining the carrier lifetime of a crystal
Assignee: Telefunken Electronic GmbH
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Filing: 1973-12-03
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Granted: 1975-11-11
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Expires: 1993-12-03
Abstract
Abstract A method for determining the carrier lifetime of a crystal comprises applying a light pulse to a photo-conductor of an intensity such that the relationship of charge carriers produced by the light action of said light pulse to the majority charge carriers present before said light pulse application is smaller than 10 3 and measuring the decay time of the photoconductor.
Inventors
- 👤 Klaus Graff
- 👤 Heinrich Pieper
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 07:42
CPC Classifications
G; G01; G01R; G01R31/00; G01R31/26; G01R31/265; G01R31/2656
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
88 words
In a method for determining the carrier lifetime of semiconductor crystals wherein the decay time of the photo conductivity of the semiconductor crystal is measured after the application of a light pulse thereto, the improvement wherein the light intensity of the light acting on the semiconductor crystal is chosen to be sufficiently small so that the relationship of the charge carriers produced by light action in the semiconductor crystal to the majority charge carriers present in the semiconductor crystal before the light action is smaller than 10 3.
Claim 2
Dependent Claim
88 words
In a method for determining the carrier lifetime of semiconductor crystals wherein the decay time of the photo conductivity of the semiconductor crystal is measured after the application of a light pulse thereto, the improvement wherein the light intensity of the light acting on the semiconductor crystal is chosen to be sufficiently small so that the relationship of the charge carriers produced by light action in the semiconductor crystal to the majority charge carriers present in the semiconductor crystal before the light action is smaller than 10 3.
Claim 3
Dependent Claim
16 words
A method as defined in claim 1, wherein luminescence diodes are used as said light source.
Claim 4
Dependent Claim
19 words
A method as defined in claim 2, wherein silicon-doped gallium arsenide luminescence diodes are used as said light source.
Claim 5
Dependent Claim
22 words
A method as defined in claim 1, wherein the electrical signal being based on the light action is summed, stored and interrogated.
Claim 6
Dependent Claim
16 words
A method as defined in claim 1, wherein the carrier lifetime of silicon crystals is determined.
Claim 7
Dependent Claim
23 words
A method as defined in claim 1, wherein the carrier lifetime of semiconductor crystals with a charge carrier concentration >1015cm 3 is determined.
Claim 8
Dependent Claim
20 words
A method as defined in claim 1, wherein the carrier lifetime of semiconductor crystals with small carrier lifetimes is determined.
Claim 9
Independent Claim
72 words
A method of determining the carrier lifetime of semiconductor crystals comprising: feeding a predetermined constant current through the semiconductor crystal; applying a light pulse to the semiconductor crystal of an intensity which causes the relationship of charge carriers produced by the light action to majority charge carriers present before the light action to be smaller than 10 3; and thereafter measuring the decay time of the resulting photoconductivity of the semiconductor crystal.
Claim 10
Independent Claim
72 words
A method of determining the carrier lifetime of semiconductor crystals comprising: feeding a predetermined constant current through the semiconductor crystal; applying a light pulse to the semiconductor crystal of an intensity which causes the relationship of charge carriers produced by the light action to majority charge carriers present before the light action to be smaller than 10 3; and thereafter measuring the decay time of the resulting photoconductivity of the semiconductor crystal.
References Cited (Backward Citations)
US3745454A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-11-10 | 1979-05-12 | 1979-11-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-11-10 | 1983-05-12 | 1983-11-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-11-10 | 1987-05-12 | 1987-11-11 | $7700.00 | Window Closed / Lapsed |