Inspection apparatus for circuit pattern

Abstract

In a circuit pattern inspection apparatus, while an electron beam is irradiated onto a surface of a substrate having a plurality of chips where circuit patterns have been formed, a signal produced from the irradiated substrate is detected so as to form an image, and then, the formed image is compared with another image in order to detect a defect on the circuit patterns. Before the electron beam is irradiated onto either the chip or the plurality of chips so as to acquire the image for an inspection purpose, an electron beam is previously irradiated onto the region to be irradiated, so that charging conditions of the substrate to be inspected are arbitrarily controlled.

1 - 6 . (canceled)  
   
   
       7 . An inspection method for inspecting circuit patterns on a substrate using an electron beam, said inspection method comprising the steps of: 
 pre-scanning the substrate by an electron beam with width of one line one time as to inspection subject chip or chips in semiconductor chips arrayed in a column where the circuit patterns have been formed, by moving a stage on which the substrate is mounted;    moving said stage by the width of one line in a direction perpendicular to the pre-scanning direction and pre-scanning said inspection subject chip or chips by said electron beam with the width of one line one time, said moving and pre-scanning step being repeatedly performed by width of said column;    scanning said inspection subject chip or chips by an electron beam with the width of one line one time in order to acquire an image;    moving said stage by the width of one line in a direction perpendicular to the scanning direction and scanning said inspection subject chip or chips by said electron beam with the width of one line one time in order to acquire the image, said moving and scanning step being repeatedly performed by width of said column; and    extracting a defect in said inspection subject chip or chips by comparing the acquired image with a standard image.    
   
   
       8 . An inspection method according to  claim 7 , further comprising the steps of: 
 post-scanning said inspection subject chip or chips by an electron beam with the width of one line one time in order to make qualities of said image uniform; and    moving said stage by the width of one line in a direction perpendicular to the post-scanning direction and post-scanning said inspection subject chip or chips by said electron beam with the width of one line one time order to make the qualities of said image uniform, said moving and post-scanning step being repeatedly performed by width of said column.    
   
   
       9 . An inspection method according to  claim 7 , wherein at least one of an acceleration voltage and irradiation current amount of said electron beam is varied between said pre-scanning and said scanning for acquiring the image.  
   
   
       10 . An inspection method according to  claim 7 , wherein the width of one line is varied between said pre-scanning and said scanning for acquiring the image.  
   
   
       11 . An inspection method according to  claim 7 , wherein adjacent lines are overlapped with each other as to a part of width direction thereof.  
   
   
       12 . An inspection method according to  claim 7 , wherein a width which is not scanned is provided between adjacent lines.  
   
   
       13 . An inspection method according to  claim 7 , wherein the moving direction of said stage during said pre-scanning is coincident with the moving direction of said stage during said scanning for acquiring the image.  
   
   
       14 . An inspection apparatus for inspecting circuit patterns on a substrate using an electron beam, said inspection apparatus comprising: 
 a control computer for causing a display unit to display an image for inputting at least one of an acceleration voltage, a current value, a successive moving direction of said substrate during scanning of said electron beam, a width of one line and a pitch of the one line width, as a condition for scanning said substrate by said electron beam and causing said electron beam to scan said substrate in accordance with the input condition;    an image processing unit for detecting secondary electrons generated from said substrate said electron beam scans to acquire an image; and    a defect judging unit for extracting an defect on said substrate by comparing the acquired image with a standard image;    wherein said control computer controls said electron beam and a stage on which said substrate is mounted in accordance with the steps of:    pre-scanning said substrate by an electron beam with width of one line one time as to inspection subject chip or chips in semiconductor chips arrayed in a column where the circuit patterns have been formed;    moving said substrate by the width of one line in a direction perpendicular to the pre-scanning direction and pre-scanning said inspection subject chip or chips by said electron beam with the width of one line one time, said moving and pre-scanning step being repeatedly performed by width of said column;    scanning said inspection subject chip or chips by an electron beam with the width of one line one time in order to acquire an image;    moving said substrate by the width of one line in a direction perpendicular to the scanning direction and scanning said inspection subject chip or chips by said electron beam with the width of one line one time in order to acquire the image, said moving and scanning step being repeatedly performed by width of said column.    
   
   
       15 . An inspection apparatus according to  claim 14 , wherein the control operation of said control computer further comprising the steps of: 
 post-scanning said inspection subject chip or chips by an electron beam with the width of one line one time order to make qualities of said image uniform; and    moving said stage by the width of one line in a direction perpendicular to the post-scanning direction and post-scanning said inspection subject chip or chips by said electron beam with the width of one line one time in order to make the qualities of said image uniform, said moving and post-scanning step being repeatedly performed by width of said column.    
   
   
       16 . An inspection apparatus according to  claim 14 , wherein at least one of the acceleration voltage and irradiation current amount of said electron beam is varied between said pre-scanning and said scanning for acquiring the image.  
   
   
       17 . An inspection apparatus according to  claim 14 , wherein the width of one line is varied between said pre-scanning and said scanning for acquiring the image.  
   
   
       18 . An inspection apparatus according to  claim 7 , wherein adjacent lines are overlapped with each other as to a part of width direction thereof.  
   
   
       19 . An inspection apparatus according to  claim 14 , wherein a width which is not scanned is provided between adjacent lines.  
   
   
       20 . An inspection apparatus according to  claim 14 , wherein the moving direction of said stage during said pre-scanning is coincident with the moving direction of said stage during said scanning for acquiring the image.