TRANSMISSION TYPE ELECTRON MICROSCOPE

摘要

PROBLEM TO BE SOLVED: To realize a transmission type electron microscope capable of obtaining transmission image information to become basis of aberration information in a short time and carrying out rapidly the correction of the aberration. SOLUTION: The electron microscope includes electron beams in which a flux of electron beams 13 narrowed down in cone shape on a reference test piece 12 is made to enter the reference test piece 12 and the incident angle expands in fan shape in irradiation direction 2. The electron beams are image-formed at positions with different distanceτfrom the center according to incident angles on a fluorescent plate 15, and the transmission image of the electron beam flux 13 is obtained, then Fourrier transform is carried out for each of a plurality of inspection regions established on the transmission image, and aberration coefficients C1, C2,,, Ciare calculated by image processing from the Fourrier transform images obtained, and the aberration of image-forming lens 14 is corrected. Therefore, the correction of aberration can be carried out by obtaining the aberration coefficients C1, C2,,, Cifrom only a sheet of transmission image, thus, the number of transmission image or its acquisition time can be reduced in the case of carrying out a high precision or high order correction to complete correction of aberration rapidly. COPYRIGHT: (C)2008,JPO&INPIT