Patent ID: 6847463
Filing Date: 2005-01-25
Classification: G01B

Abstract:
1. A method for detecting carbon deposits and/or oxide deposits on the surface of a substrate that comprises the steps of: (a) selecting a detection radiation such that (i) the intensity of the detection radiation that is reflected from the carbon deposits is lower than the intensity of detection radiation that is reflected from a bare surface of the substrate, which does not contain either carbon or oxide deposits, and (ii) the intensity of the detection radiation that is reflected from the oxide deposits is higher than the intensity of detection radiation that is detected from a bare surface; (b) irradiating the surface of the substrate with incident detection radiation which as a first intensity; (c) measuring the intensity level of the reflected detection radiation from the surface which has a second intensity level; and (d) calculating the difference between the first intensity level and the second intensity level to detect the presence of carbon deposits and/or oxide deposits.