Pattern inspection method and its apparatus

Abstract

A pattern inspection method and apparatus are provided for sequentially imaging plural chips formed on a substrate to be inspected to and obtaining inspection images and reference images, calculating a position gap between the inspection images and the reference images using a recipe created in advance by using another substrate of the same kind or type as the substrate, the recipe including information for determining which pattern sections are to be selected and discarded, aligning the inspection images and the reference images using information of the position gap from the calculating step, and comparing the inspection images with the reference images aligned by the aligning step and extracting a defect candidate.

1 . A pattern inspection method comprising the steps of:
 sequentially imaging plural chips formed on a substrate to be inspected and obtaining inspection images and reference images;   calculating a position gap between the inspection images and the reference images obtained by the imaging step by using a recipe which is created in advance by using another substrate different from the substrate to be inspected, the another substrate being the same kind or type as the substrate, the recipe including information for determining which pattern sections are to be selected and other pattern sections to be discarded;   aligning the inspection images and the reference images by using information of the position gap from the calculating step; and   comparing the inspection images with the reference images aligned by the aligning step and extracting a defect candidate.   
     
     
         2 . The pattern inspection method according to  claim 1 ,
 wherein the another substrate is run through a same process as the substrate.   
     
     
         3 . The pattern inspection method according to  claim 1 ,
 wherein in the calculating step, calculating the position gap is done based on the recipe which further includes a calculating process.   
     
     
         4 . The pattern inspection method according to  claim 1 ,
 wherein in the calculating step, calculating the position gap is done in accordance with an order of calculating to be determined in the recipe.   
     
     
         5 . A pattern inspection apparatus comprising:
 an image acquisition unit to sequentially detect inspection images and reference images of a substrate on which plural chips are formed;   a calculating unit to calculate a position gap between the inspection images and the reference images obtained by the image acquisition unit, by using a recipe which is created in advance by using another substrate different from the substrate to be inspected, the another substrate being the same kind or type as the substrate, the recipe including information for determining which pattern sections are to be selected and other pattern sections to be discarded;   an aligning unit to align the inspection images with the reference images by using information of the position gap by the calculating unit; and   a defect candidate extracting unit to compare the inspection images with the reference images aligned by the aligning unit and to extract a defect candidate.   
     
     
         6 . The pattern inspection apparatus according to  claim 5 ,
 wherein the image acquisition unit comprising:   a light source to irradiate light on the substrate;   an image sensor to detect image front light reflected from the substrate and to divide the image into a plurality of pattern sections.   
     
     
         7 . The pattern inspection apparatus according to  claim 5 ,
 wherein the another substrate has been run through a same process as the substrate.   
     
     
         8 . The pattern inspection apparatus according to  claim 5 ,
 wherein in the calculating unit, calculating the position gap is based on the recipe which further includes a calculating process.   
     
     
         9 . The pattern inspection apparatus according to  claim 5 ,
 wherein in the calculating unit, calculating the position gap is done in accordance with an order of calculating to be determined in the recipe.   
     
     
         10 . A pattern inspection apparatus comprising:
 means for sequentially imaging plural chips formed on a substrate to be inspected and obtaining inspection images and reference images;   means for calculating a position gap between the inspection images and the reference images obtained by the imaging step by using a recipe which is created in advance by using another substrate different from the substrate to be inspected, the another substrate being the same kind or type as the substrate, the recipe including information for determining which pattern sections are to be selected and other pattern sections to be discarded;   means for aligning the inspection images and the reference images by using information of the position gap from the calculating step; and   means for comparing the inspection images with the reference images aligned by the aligning step and extracting a defect candidate.   
     
     
         11 . The pattern inspection apparatus according to  claim 7 ,
 wherein the another substrate is run through a same process as the substrate.   
     
     
         12 . The pattern inspection apparatus according to  claim 7 ,
 wherein the calculating means includes means for calculating the position gap based on the recipe which further includes a calculating process.   
     
     
         13 . The pattern inspection apparatus according to  claim 7 ,
 wherein in means further includes means for calculating the position gap in accordance with an order of calculating to be determined in the recipe.   
     
     
         14 . The pattern inspection apparatus according to  claim 10 ,
 wherein the means for sequentially imaging plural chips comprises:   light source means for irradiating light on the substrate; and   image sensor means for detecting image front light reflected from the substrate and dividing the image into a plurality of pattern sections.