SCAN DEVICE

摘要

A probe needle (2) is successively moved to a plurality of measurement points set in a measurement region on a sample (S) so as to measure a z-displacement amount. An excitation control unit (4) feedback-controls a piezoelectric element (3) so that a vibration amplitude of a cantilever (1) is constant in accordance with the detection output by a displacement detection unit (8). Moreover, a vertical displacement control unit (11) feedback-controls a vertical position scan unit (6) so as to obtain a constant distance between the probe needle (2) and the sample (S) according to a frequency shift by a frequency detection unit (9). When changes of outputs of two feedback loops at a certain measurement point are both within a predetermined range, a main control unit (12) issues an instruction to a horizontal position control unit (11) to rapidly move to the next measurement point. As a result, it is possible to adaptively decide such a measurement time that both of the two feedback controls at respective measurement points are established. This eliminates an unnecessary measurement time, which in turn reduces the time required for creating one convex/concave image as compared to the conventional technique and improves the throughput.