Defect Inspection Tool For Sample Surface And Defect Detection Method Therefor

Abstract

A defect inspection tool includes an illumination optical system for irradiating light to a surface of an object, and a detection optical system for detecting light scattered from the surface of the object which is irradiated. The detection optical system include an analyzer, a photoelectric converting device for receiving the scattering light passed through the analyzer, a member for saving a database prepared through an actual measurement or a calculation in correspondence with a condition of the illumination optical system, that of the detection optical system, a kind of an object to be inspected, and a rotation angle of the analyzer, and a member for adjusting an angle of the analyzer by selecting an angle of the analyzer from a database saved in the member for saving on a basis of an inspection recipe after receiving the inspection recipe to the defect inspection tool.

1 . A defect inspection tool comprising:
 an illumination optical system for irradiating an illuminating light to a surface of an object to be inspected; and   a detection optical system for detecting a scattering light scattered from the surface of the object to be inspected being irradiated by the illumination optical system;   wherein the detection optical system includes:   an analyzer;   a photoelectric converting device for receiving the scattering light passed through the analyzer;   a member for saving a database prepared through an actual measurement or a calculation in correspondence with a condition of the illumination optical system, that of the detection optical system, a kind of an object to be inspected, and a rotation angle of the analyzer; and   a member for adjusting an angle of the analyzer by selecting an angle of the analyzer from a database saved in the member for saving on a basis of an inspection recipe after receiving the inspection recipe to the defect inspection tool.   
   
   
       2 . The defect inspection tool according to  claim 1 , further comprising:
 a signal processing circuit for processing a signal based on a scattering light received by the photoelectric converting device and for inspecting a defect of the surface of the objected to be inspected.   
   
   
       3 . The defect inspection tool according to  claim 1 , further comprising:
 a scattering light irradiated by the illumination optical system and scattered from a surface of the object to be inspected includes a first scattering light scattered from a defect or a foreign substance of the surface of the object to be inspected, and a second scattering light scattered from a roughness of the surface of the object to be inspected.   
   
   
       4 . The defect inspection tool according to  claim 1 , wherein the analyzer is rotatable with respect to an optical center axis of the scattering light scattered from a surface of the object to be inspected. 
   
   
       5 . The defect inspection tool according to  claim 3 , wherein the analyzer is so arranged as to pass through the first scattering light. 
   
   
       6 . The defect inspection tool according to  claim 1 , wherein the photoelectric converting device converts a scattering light being received into a electrical signal. 
   
   
       7 . The defect inspection tool according to  claim 1 , wherein the photoelectric converting device is one of a TV camera, a CCD linear sensor, a TDI sensor, and a photoelectric multiplier tube. 
   
   
       8 . The defect inspection tool according to  claim 1 ,
 wherein a position of the detection optical system is determined by an angle of elevation and an angle of orientation of the detection optical system in correspondence with the surface of the object to be inspected;   wherein an inspection condition is determined by an angle of elevation and polarization direction of the illumination optical system in correspondence with the surface of the object to be inspected; and   wherein a special feature corresponding to a kind of the object to be inspected is determined by a complex index of a film material of the object to be inspected.   
   
   
       9 . The defect inspection tool according to  claim 1 ,
 wherein a rotation angle of the analyzer of the database is an angle at which the ratio between a detection signal based on a scattering light scattered from a roughness of the surface of the object to be inspected and a detection signal based on a scattering light scattered from a defect of the surface of the object to be inspected becomes a maximum.   
   
   
       10 . A defect detection method including:
 an illumination step for irradiating a illumination light to a surface of an object to be inspected; and   a detection step for detecting a scattering light irradiated in the illumination step, and scattered from a surface of the object to be inspected;   wherein the detection step includes:   a step for passing through a part of the scattering light out of the scattering light scattered from the object to be inspected by using the analyzer;   a light receiving step for receiving a scattering light passed through in the step for passing through a part of the scattering light;   a step for receiving an inspecting receipt to the defect inspection tool; and   an adjusting step for adjusting the angle of the analyzer by selecting the angle of the analyzer from a database prepared through an actual measurement or a calculation in correspondence with a condition of the illumination in the illumination step, a condition of detection in the detection step, a kind of an object to be inspected, and a rotation angle of the analyzer according to the inspection receipt received in the receiving step.   
   
   
       11 . The defect detection method according to  claim 10 , further comprising:
 a signal processing step for processing a signal based on a scattering light received by the photoelectric converting device and for inspecting a defect of the surface of the object to be inspected.   
   
   
       12 . The defect detecting method according to  claim 10 , wherein in the step for passing through a part of the scattering light, the analyzer is provided to be rotatable with respect to an optical center axis of the scattering light scattered from a surface of the object to be inspected. 
   
   
       13 . The defect detection method according to  claim 10 , wherein in the adjusting step for adjusting an angle of the analyzer, the analyzer is so adjusted as to have an angle at which the ratio between a detection signal based on a scattering light scattered from a roughness of the surface of the object to be inspected and a detection signal based on a scattering light scattered from a defect of the surface of the object to be inspected becomes maximum.