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:
Sep. 17, 2002
Filed:
Apr. 13, 2000
Vittorio Sirtori, Milan, IT;
Lorenza Lombardi, Lissone, IT;
Michele Monopoli, Milan, IT;
Franco Zambon, Milan, IT;
International Business Machines Corporation, Armonk, NY (US);
Abstract
A method and system for estimating the roughness and the contamination of a surface. A preferred embodiment of the present invention makes use of a mathematical model which gives indications of the metal roughness, expressed as the ratio of metal volume to air volume, and the contamination thickness values of a metal substrate (e.g. gold) for a determined contamination (e.g. organic). This model is based on a series of tables which represent the expected values of &psgr;, i.e. the ratio between the amplitudes of the incident beam on the two polarization planes multiplied by the ratio of the amplitudes of the reflected beam on the polarization planes, and &Dgr;, i.e. the difference between the phases on the two polarization planes of the incident beam and the reflected beam, for a gold substrate having a predetermined roughness and a predetermined type of contamination (organic). Each table is built for a roughness value &phgr; expressed as the ratio of metal volume to air volume and gives the values of &psgr; and &Dgr; for a range of possible contaminations expressed as thickness of the contaminant film. Each table shows, for a predetermined value of &phgr;, the expected values of &psgr; and &Dgr; for an organic contaminant film having a thickness of 0, 10 . . . 100 Angstrom.