Patent ID: 7471382
Filing Date: 2008-12-30
Classification: G01N

Abstract:
1. A surface inspection method for detecting anomalies on a surface, comprising: causing relative motion between a beam of radiation and the surface; collecting radiation scattered from the surface and directing the collected radiation to one or more channels; converting the collected radiation carried by at least one of the channels into respective signals; determining presence of potential anomalies in or on the surface from said signals; storing information in the signals converted from radiation scattered from locations of the surface determined to have potential anomalies and information in the signals converted from radiation scattered from portions of the surface adjacent to such locations and not determined to have potential anomalies; designating dimensions of an area prior to the collecting and converting, wherein the storing stores at least information in signals converted from radiation scattered from different pixels that are on the surface and that are within one or more areas of the designated dimensions, each of said areas containing a location on the surface where a potential anomaly is determined to be present; and erasing stored information in signals converted from radiation scattered from portions on the surface only when such portions are not within any one of the areas each containing a location on the surface where a potential anomaly is determined to be present.