Surface defect inspection method and apparatus

Abstract

A surface defect inspection apparatus and method is provided which illuminates a plurality of beams set to different intensity values to a sample. Scattered light from the plurality of beams is detected and processed to analyze the surface defects.

What we claim is: 
     
         1 . A defect inspection apparatus comprising:
 An illumination optical system configured to illuminate a plurality of beams set to different intensity values to a sample;   a detection optical system configured to detect a scattered light from the sample; and   a processing system configured to process a signal from the scattered light.   
     
     
         2 . A defect inspection apparatus according to  claim 1 ,
 wherein the illumination optical is configured to illuminate the plurality of beams to the sample simultaneously.   
     
     
         3 . A defect inspection apparatus according to  claim 1 ,
 wherein the illumination optical system is configured to illuminate the plurality of beams to different regions of the sample.   
     
     
         4 . A defect inspection apparatus according to  claim 1 ,
 wherein the plurality of beams are arrayed on a surface of the sample.   
     
     
         5 . A defect inspection apparatus according to  claim 1 ,
 wherein the illumination optical system having a polarizer, and wherein the polarizer is configured to divide at least one of the beams into linearly polarized beams which are orthogonal with each other.   
     
     
         6 . A defect inspection apparatus according to  claim 5 ,
 wherein the polarizer comprises a Wallaston prism.   
     
     
         7 . A defect inspection apparatus according to  claim 1 ,
 wherein the illumination optical system is configured to enable adjusting a distance between the plurality of beams.   
     
     
         8 . A defect inspection apparatus according to  claim 1 ,
 wherein the illumination optical system is configured to illuminate the plurality of beams from a same direction.   
     
     
         9 . A defect inspection apparatus according to  claim 1 ,
 wherein the illumination optical system is configured to illuminate the plurality of beams from different directions.   
     
     
         10 . A defect inspection apparatus according to  claim 1 ,
 wherein the illumination optical system includes a first optical system and a second optical system which have different elevation angles to a surface of the sample.   
     
     
         11 . A defect inspection method comprising:
 illuminating a plurality of beams set to different intensity values to a sample; detecting a scattered light from the sample; and   processing a signal from the scattered light.   
     
     
         12 . A defect inspection method according to  claim 11 ,
 further comprising illuminating the plurality of beams simultaneously.   
     
     
         13 . A defect inspection method according to  claim 11 ,
 further comprising illuminating the plurality of beams to different regions of the sample.   
     
     
         14 . A defect inspection method according to  claim 11 ,
 further comprising illuminating an arrayed plurality of beams.   
     
     
         15 . A defect inspection method according to  claim 11 ,
 further comprising dividing at least one of the beams into linearly polarized beams which are orthogonal with each other.   
     
     
         16 . A defect inspection method according to  claim 15 ,
 wherein the polarizer comprises a Wallaston prism.   
     
     
         17 . A defect inspection method according to  claim 11 ,
 further comprising adjusting a distance between the plurality of beams.   
     
     
         18 . A defect inspection method according to  claim 11 ,
 further comprising illuminating the plurality of beams from a same direction.   
     
     
         19 . A defect inspection method according to  claim 11 ,
 further comprising illuminating the plurality of beams from different directions.