Patent ID: 7286218
Filing Date: 2007-10-23
Classification: G01N,G06T,Y10T

Abstract:
1. A method for inspecting a surface of a workpiece, the method comprising: scanning an incident beam on the surface of the workpiece to impinge thereon to create reflected light and scattered light comprising light that is scattered from the surface upon impingement thereon by the incident beam; determining an extent of a contribution to surface roughness from a component of the surface, with the component having a surface roughness spatial frequency range; wherein determining an extent of a contribution to surface roughness from a component of the surface further comprises determining the in-scan surface structure spatial frequency responses of a set of selected collectors, each of the selected collectors positioned at a known collection position above the surface, the in-scan surface structure spatial frequency responses comprising responses to scattered light that is formed by impinging on the surface an incident beam that is applied at a selected angle from normal onto the surface; comprising light that is scattered from the surface upon impingement thereon by the incident beam; determining a response range for the range of the in-scan surface structure spatial frequency response; determining a scatter intensity value representative of the response range in order to determine a representative extent of contribution to surface roughness of the surface; scanning the incident beam on the surface of the workpiece to impinge thereon to create scattered light comprising light that is scattered from the surface upon impingement thereon by the incident beam; and determining a scatter intensity value for each collector in the set of selected collectors, and comparing scatter intensity values in order to build an understanding of the haze response by the surface to impingement of an incident beam thereon.