Automatic focusing system for scanning electron microscope equipped with laser defect detection function

A particle defect examination apparatus comprising a scanning electron microscope equipped with a laser defect detection function by use of an optical microscope, the particle defect examination apparatus comprising:

• a storage device that stores an accurate offset amount between focal positions of the optical microscope and the scanning electron microscope;
• an analysis device that performs an analysis to find a focused position of the optical microscope based on a laser dark-field image obtained by the optical microscope;
• and
• a device that automatically adjusts a focus of the scanning electron microscope by adding a readjusted amount of the focus of the optical microscope to the offset amount.

A particle defect examination apparatus comprising:

• an optical microscope that photographs an image of at least one defect;
• a scanning electron microscope;
• a storage device that stores an accurate offset amount between focal positions of the optical microscope and the scanning electron microscope;
• an analysis device that analyzes the image to readjust a focused position of the optical microscope;
• and
• a device that automatically adjust a focus of the scanning electron microscope by adding a readjusted amount of the focused position of the optical microscope to the offset amount.