| 摘要 |
PROBLEM TO BE SOLVED: To measure a dimension of a pattern on a sample with high throughput. SOLUTION: The apparatus 10 for measuring a dimension of a pattern comprises a stage 3, an electron gun 11, electronic lens systems 22 to 24 each having an MOL(moving objective lens) mechanism to scan an electron beam 6 on a sample 5, a secondary electron detector 31 for detecting secondary electron or the like emitted from the sample 5, and a host computer 4 having a pattern dimension calculator 16. In this case, the stage 3 is moved at an equal speed. Coordinates of the stage are measured in real time by a laser interferometer 41. A change of an operating distance of the beam 6 is measured in real time from a focal distance measuring unit 44 by an optical lever system, and they are respectively fed back to a stage controller 13 and an objective lens 24. When the pattern to be measured arrives at an area to be able to be scanned, the beam 6 is scanned in a best focus while moving a scanning starting position of the beam in synchronization with the equal speed moving of the stage, thereby acquiring its SEM image.
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