The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Aug. 24, 1982
Filed:
Feb. 28, 1980
Filbert J Bartoli, Upper Marlboro, MD (US);
Jerry R Meyer, Baltimore, MD (US);
The United States of America as represented by the Secretary of the Navy, Washington, DC (US);
Abstract
A method for accurately determining the compensation density of n-type naw-gap semiconductors. A semiconductor sample is irradiated with laser pulses of a particular density and pulse width for a particular time length with the sample maintained at a low temperature to generate photo-excited carriers within the semiconductor sample. Photons of energy less than the energy gap, E.sub.g, but greater than, E.sub.g /2, generate carriers uniformly throughout the semiconductor via the nonlinear mechanism of two-photon absorption. Photo-Hall measurements are made on the semiconductor sample during and after the laser pulse to determine the mobility, .mu., and carrier density, n, as a function of time using suitable equipment such as a computer controlled digital processing oscilloscope to display the curves. The curves displayed by the oscilloscope are compared with previously calculated curves to obtain a match and thereby determine the quality of the sample. By combining measurements of the Hall effect and conductivity, one can deduce the carrier densities and mobilities as well as other various quantities by well-known formulas.