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:
Jun. 16, 1981
Filed:
Jan. 17, 1977
Richard W Gurtler, Mesa, AZ (US);
Motorola, Inc., Schaumburg, IL (US);
Abstract
A method for the measurement of minority carrier lifetime in semiconductor wafers, sheets and ribbons by purely optical means. The method does not require electrical or MOS contacts to the wafer, nor does it require any specific processing to facilitate measurement. The technique is non-destructive, and is applicable to any semiconductor wafer, with or without surface dielectric films (e.g., SiO.sub.2, Si.sub.3 N.sub.4, Ta.sub.2 O.sub.5) as long as it has no metal films. This technique is fast, accurate, and of reasonable high resolution, so that it may be applied to evaluate the effects of specific process steps (e.g., ribbon growth, diffusion, oxidation, ion implantation, delectric deposition, annealing) in real time and hence serve as a production control technique as well as a research tool. By utilizing reasonable equipment sophistication, this technique should enable the measurement of lifetime over a wide range of values, covering the scale from high-speed bipolar devices and integrated circuits (.about.10.sup.-9 s) to power transistors and solar cells (.about.10.sup.-3 s).