METHOD OF VISUALIZING DEFECT USING DESIGN DATA AND DEFECT DETECTION METHOD

1 . A method of visualizing a defect, comprising:

generating pattern images with a scanning electron microscope;

superimposing the pattern images while aligning positions of patterns in the pattern images;

calculating a variance of gray level over the pattern images for each of inspection areas on the patterns;

creating a false-color image by color-coding the inspection areas according to magnitude of the variance; and

displaying the false-color image.

2 . The method of visualizing a defect according to claim 1 , wherein the inspection areas are established in advance based on shape of the patterns contained in a design data.

3 . The method of visualizing a defect according to claim 1 , wherein at least one of the inspection areas is an area on an edge of the patterns.

4 . A defect detection method comprising:

generating pattern images with a scanning electron microscope;

superimposing the pattern images while aligning positions of patterns in the pattern images;

producing data of gray levels for each of inspection areas on the patterns by obtaining gray levels over the pattern images for each of the inspection areas;

determining threshold values corresponding respectively to the inspection areas, based on the data of gray levels;

comparing a gray level of each one of pixels in the inspection areas with a corresponding threshold value of the threshold values;

applying a first color to pixels having gray levels higher than the threshold value, and applying a second color to pixels having gray levels lower than the threshold value, thereby generating a binary image; and

detecting a pattern defect by detecting connected pixels of the first color whose number is equal to or greater than a set number.

5 . The defect detection method according to claim 4 , wherein each of the threshold values is determined based on a quartile range or a standard deviation of the data.