| 摘要 |
PURPOSE:To facilitate the detection of a second reference pattern by making an approximate correction of a moving quantity in consideration of an inclination worked out by a first reference pattern before a sample table is moved from the first reference pattern to the second reference pattern on a sample. CONSTITUTION:On an Si wafer 14, cross-shaped reference patterns 22 and 23 of the same shape are formed. Electron beams 15 from a control circuit 21 scan as 24, 25, and 26 and a pattern center position O1 is calculated from detected positions A, B, C and D. Furthermore, respective positions P and Q are worked out and an inclination of the pattern 22 regarding a sample table moving direction is worked out from the resultant positions. Next, the control circuit 21 moves a sample table in consideration of the inclination thus obtained and the reference pattern 23 can be also arranged in a deflection region of the electron beams. As for the second reference patterns 23, the same treatment as in case of the first reference pattern 22 is carried out to work out a center position O2. Lastly, an inclination of an Si wafer is worked out accurately from the center positions O1 and O2.
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