Patent ID: 7659508

Claim:
A scanning electron microscope comprising: an electron source; a deflector for scanning an electron beam emitted from said electron source in an X-direction and a Y-direction which is orthogonal thereto; a detection means for detecting an electron generated from a sample by irradiating said electron beam on said sample; a display for displaying a pattern image based on said electron generated from said sample; and a control device for measuring a dimension of said pattern image displayed on said display, wherein said control device has a memory unit for storing a plurality of combinations of a measuring magnification in said X-direction and a magnification in said Y-direction, which is smaller than said measuring magnification in said X-direction, and controls said deflector so as to deflect said electron beam to form a rectangle of said pattern image having a short side in said X-direction and a long side in said Y-direction by selecting one of said combinations, and said display displays the pattern image of an irradiation area which has a side in said Y-direction that is longer than a sede in said X-direction in a display range, a ratio of a length of said side in said Y-direction to a length of said side in said X-direction of the display range being smaller than a ratio of a length of a side in said Y-direction to a length of said sede in said X-direcition of the irradiation area, and said dimension of said pattern image in said X-direction is measured based on said pattern image displayed in said display range, and so as to display said pattern image as the magnification in said X-direction becomes higher than the magnification in said Y-direction.