Method and Its Apparatus for Inspecting Particles or Defects of a Semiconductor Device

Abstract

Conventionally, a particle/defect inspection apparatus outputs a total number of detected particles/defects as the result of detection. For taking countermeasures to failures in manufacturing processes, the particles/defects detected by the inspection apparatus are analyzed. Since the inspection apparatus outputs a large number of detected particles/defects, an immense time is required for analyzing the detected particles/defects, resulting in a delay in taking countermeasures to a failure in the manufacturing processes. In the present invention, an apparatus for optically inspecting particles or defects relates a particle or defect size to a cause of failure in an inspection result. A data processing circuit points out a cause of failure from the statistics on the inspection result, and displays information on the inspection result. A failure analysis is conducted by setting a threshold for identifying a failure in each of regions on a semiconductor device or the like to statistically evaluate detected particles.

1 - 6 . (canceled) 
     
     
         7 . An apparatus for inspecting particles or defects, the apparatus comprising:
 an illuminating unit which obliquely irradiates light to an object under inspection;   a light detecting unit which detects light scattered from the object under inspection by the oblique irradiation from the illuminating unit; and   a signal processing unit which detects particles or defects on the object under inspection by processing a signal detected by the light detecting unit;   wherein the signal processing unit is arranged to calculate the dimension of the particles or defects in accordance with a number of pixels of image of the light having been scattered at the object under inspection.   
     
     
         8 . The apparatus according to claim  1 , wherein the signal processing unit is arranged to determines that signal intensity corresponding to the detected particles or defects is larger than a predetermined value in case that an amount of pixels of the image exceeds a predetermined number. 
     
     
         9 . The apparatus according to claim  1 , wherein the signal processing unit is arranged to determines that signal intensity corresponding to the detected particles or defects is larger than a predetermined value in case that an amount of pixels of the image exceeds a predetermined number, and to compensate the signal intensity having been determined. 
     
     
         10 . The apparatus according to claim  1 , wherein the signal processing unit is arranged to calculate the dimension of the particles or defects in accordance with a number of contrast values of the pixels of the image of the light having been scattered at the object under inspection. 
     
     
         11 . The apparatus according to  claim 10 , wherein the number of contrast values of the pixels of the of the image of the light having been scattered a the object under inspection comprises a total amount of contrast values. 
     
     
         12 . The apparatus according to claim  1 , wherein the signal processing unit is arranged to compensate the signal intensity, and to calculate the dimension of the particles or defects in accordance with the signal intensity having been compensated. 
     
     
         13 . A method of inspecting particles or defects, the apparatus comprising:
 obliquely irradiating light to an object under inspection;   detecting light scattered from the object under inspection by the oblique irradiation from an illuminating unit;   detecting particles or defects on the object under inspection by processing a signal detected by a light detecting unit; and   calculating the dimension of the particles or defects in accordance with a number of pixels of image of the light having been scattered at the object under inspection.   
     
     
         14 . The method according to  claim 13 , further comprising determining that signal intensity corresponding to the detected particles or defects is larger than a predetermined value in case that an amount of pixels of the image exceeds a predetermined number. 
     
     
         15 . The method according to  claim 13 , further comprising determining that signal intensity corresponding to the detected particles or defects is larger than a predetermined value in case that an amount of pixels of the image exceeds a predetermined number, and to compensate the signal intensity having been determined. 
     
     
         16 . The method according to  claim 13 , further comprising calculating the dimension of the particles or defects in accordance with a number of contrast values of the pixels of the image of the light having been scattered at the object under inspection. 
     
     
         17 . The method according to  claim 16 , wherein the number of contrast values of the pixels of the of the image of the light having been scattered a the object under inspection comprises a total amount of contrast values. 
     
     
         18 . The method according to  claim 13 , further comprising:
 compensating the signal intensity; and   calculating the dimension of the particles or defects in accordance with the signal intensity having been compensated.