Patent ID: 8260035
Filing Date: 2012-09-04
Classification: G01N,G06K

Abstract:
1. A method for inspecting a surface of a semiconductor workpiece, the method comprising: providing a surface inspection system and using the surface inspection apparatus to cause laser light to impinge upon a test location on the workpiece surface and thereby cause the laser light to emerge from the surface as returned light comprising at least one of reflected light and scattered light; collecting the returned light and generating a signal from the returned and collected light, the signal comprising a signal value representative of a characteristic of the workpiece surface at the test location; providing a plurality of defect threshold candidates, the violation of which indicates the presence of a preexisting defect on the workpiece, receiving with the surface inspection system an input from a user, where the input represents a desired sensitivity for the inspection of the workpiece, causing the surface inspection system to automatically select a threshold from among the plurality of defect threshold candidates based on the input from the user and a plurality of prior signal values from secondary test locations, such that the threshold selected for the test location is different from the threshold selected for a different test location on the workpiece; comparing the threshold to the signal value to obtain a difference value; using the difference value to assess the characteristic of the workpiece surface at the test location; and using the surface inspection system to automatically cause the method to be repeated for a plurality of test locations on the workpiece surface.