Method and apparatus for reviewing defects

A method of reviewing a defect, comprising the steps of:

• picking up an image of an area including a defect candidate on a sample by use of information of a defect detected by beforehand inspecting the sample, whose surface is provided with a pattern, by another inspection device to acquire the image of the area including a defect having a first magnification;
• comparing the acquired image of the area including the defect having the first magnification with a reference image having the first magnification to extract a defect;
• picking up an image of an area including the extracted defect to acquire an image of an area including a defect having a second magnification which is larger than the first magnification;
• comparing the acquired image of the area including the defect having the second magnification with a reference image having the second magnification to extract a defect;
• and
• classifying the extracted defects depending on characteristic amounts of the defects,
• wherein the second magnification reference image is an image prepared by estimating a non-defective state which does not include any defect from the acquired image of the area including the first magnification defect and the acquired image of the area including the second magnification defect.

An apparatus for reviewing a defect on a sample, comprising:

• image acquiring means for picking up an image of the sample to acquire an image of the surface of the sample;
• table means for disposing the sample and controlling a position of the sample so that a desired area picture of the sample enters an image pickup view field of the image acquiring means;
• image processing means for processing the image obtained by picking up, by the image acquiring means, an image of the desired area on the sample whose position is controlled by the table means;
• and
• control means for controlling the image acquiring means, the table means, and the image processing means;
• wherein the control means controls the position of the table means so that the defect enters the view field of the image acquiring means by use of information of the defect detected by beforehand inspecting the sample with another inspection device, and
• the image processing means compares an image of an area including a defect having a first magnification acquired by the image acquiring means with a reference image having the first magnification to extract a defect, compares an image of an area including the defect obtained by picking up, by the image acquiring means, an image of an area including the extracted defect at a second magnification which is larger than the first magnification with a reference image having the second magnification prepared by estimating a non-defective state which does not include any defect from an image of an area including the defect to extract a defect, and classifies the extracted defects depending on characteristic amounts of the defects.

An apparatus for reviewing a defect on a sample, comprising:

• image acquiring means for picking up an image of the sample to acquire an image of the surface of the sample;
• table means for disposing the sample and controlling a position of the sample so that a desired area picture of the sample enters an image pickup view field of the image acquiring means;
• image processing means for processing the image obtained by picking up, by the image acquiring means, an image of the desired area on the sample whose position is controlled by the table means;
• and
• control means for controlling the image acquiring means, the table means, and the image processing means;
• wherein the image processing means comprises:
• a non-defective state estimation calculating function section for estimating a non-defective state of a defective portion in which the defect exists by use of the image including the defect acquired by the image acquiring means to synthesize a reference image;
• and
• a defect classifying function section for comparing the reference image synthesized by the non-defective state estimation calculating function section with the image including the defect acquired by the image acquiring means to detect defects, and classifying the detected defects.