| 摘要 |
PURPOSE:To increase the speed of detection of a pattern by carrying out the detection without stopping a sample table by continuously moving the sample table and scanning a load beam over a right position on a sample according to the positional information of the sample table. CONSTITUTION:A sample table 6 at first begins to move from the point (X01, Y01) to the point (X01, Y01) according to a command from a sample-table-controlling device 8. At this point, the reference point (X01, Y01) of the first rectangular area is sent to an arithmetic unit 7 by means of a rectangular area reference point assigning device 9. After the smaple table 6 starts to move, coordinates (X, Y) specifying the position of the sample table 6 are measured by the actual time by means of a sample-table-position-measuring device 5 before being sent to the arithmetic unit 7 as necessary. The arithmetic unit 7 computes the reference point (X0m, Y0n) of a rectangular area which is to be used as an input as well as the positional gap between the sample table 6 and the rectangular area at that point. A reference deflection signal produced by a deflection-signal producer 1 and a beam-position-correcting signal are added by an adder 2 so as to deflect a load beam toward a right rectangular area through a deflecting amplifier 3 and a deflecting coil 4. |
