Defect observing electron microscope

A transmission electron microscope for observing defects in a specimen to be examined, comprising:

• an electron gun for electron beam emission;
• a first electron lens system for illuminating an electron beam emitted by said electron gun to a specimen illuminating position;
• a second electron lens system for focusing the electron beam passing through the specimen onto a predetermined image plane;
• a pair of detachable specimen holders adjacently arranged at upper and lower stages separated by a small distance respectively along an electron beam axis, wherein a first one of said holders holds a specimen to be examined for defects and a second one of said holders holds a reference specimen free from defects;
• and
• means for independently positioning specimens held by said first and second specimen holders into the electron beam illuminating position to create a moire fringe at said image plane that magnifies defects in a specimen to be examined.

A method for observing defects in a specimen to be examined with a transmission electron beam microscope, comprising:

• emitting an electron beam from an electron gun through a first electron lens system for illuminating specimens held in a specimen illuminating position;
• focusing the electron beam passing through the specimen illuminating position onto a predetermined image plane with a second electron lens system;
• providing a pair of detachable specimen holders adjacently arranged at upper and lower stages separated by a small distance respectively along an electron beam axis, wherein a first one of said holders holds a specimen to be examined for defects and a second one of said holders holds a reference specimen free from defects;
• and
• independently positioning specimens held by said first and second specimen holders into the electron beam illuminating position to create a moire fringe at said image plane that magnifies defects in a specimen to be examined.

A system for searching for defects in a specimen using a transmission electron microscope, comprising:

• an electron gun for electron beam emission;
• a first electron lens system for illuminating an electron beam emitted by said electron gun to a specimen illuminating position;
• a second electron lens system for focusing the electron beam passing through the specimen onto a predetermined image plane;
• means for controlling the magnification of the electron microscope;
• a pair of detachable specimen holders adjacently arranged at upper and lower stages separated by a small distance respectively along an electron beam axis, wherein a first one of said holders holds a specimen to be examined for defects and a second one of said holders holds a reference specimen free from defects;
• means for independently positioning specimens held by said first and second specimen holders into the electron beam illuminating position to create an observation moire fringe at said image plane that magnifies defects in a specimen to be examined, including moving the specimen to be examined relative to the reference specimen while keeping the electron microscope at a low magnification with said magnification controlling means;
• means for deciding whether a defect exists in the specimen to be examined by comparing patterns of the observation moire fringe with a standard pattern a moire fringe pattern from defects;
• and
• means connected to said positioning means for stopping the movement of the specimen to be examined when said defect determining means determines that a defect exists.