Electricity: measuring and testing – Measuring – testing – or sensing electricity – per se – With rotor
Patent
1984-12-18
1987-04-28
Eisenzopf, Reinhard J.
Electricity: measuring and testing
Measuring, testing, or sensing electricity, per se
With rotor
324158R, G01R 3126
Patent
active
046617701
ABSTRACT:
A direct band-gap semiconductor (54) is exposed to intensity-modulated photon radiation (56) having a characteristic energy at least as great as the energy gap of the semiconductor. This produces a time-dependent concentration of excess charge carriers through the material, producing a luminescence signal (58) modulated at the same frequency as the incident radiation but shifted in phase by an amount related to the lifetime of minority carriers. In a preferred embodiment, the phase shift of the luminescence signal is determined by transforming it to a modulated electrical signal and mixing the electrical signal with a reference signal modulated at the same frequency and having a phase which is known relative to the incident radiation. Minority carrier lifetime is calculated by integrating a direct current component of the mixed signal (F.sub.dc) over a 2.pi. range in phase of the reference signal.
REFERENCES:
patent: 3886370 (1975-05-01), Schubert et al.
patent: 3919639 (1975-11-01), Graff et al.
patent: 3982184 (1976-09-01), Sanderson
patent: 4122383 (1978-10-01), von Roos
patent: 4286215 (1981-08-01), Miller
patent: 4374328 (1983-02-01), Tekippe et al.
patent: 4551674 (1985-11-01), Miller
"Two-Chopper Technique for Measuring Fluorescence Lifetimes", by Ingersoll, 1/76, Applied Optics, vol. 15, #1, pp. 61-63.
O. von Roos, J. Appl. Phys. 50, 3738 (1979).
Weiner et al., J. Appl. Phys. 55, 3889 (1984).
O. von Roos, J. Appl. Phys. 54, 1389, 2495 (1983).
Burns W.
Eisenzopf Reinhard J.
Jones Thomas H.
Manning John R.
McCaul Paul F.
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