Patent ID: 7814775

Claim:
An apparatus for controlling a Z-position of a probe, said apparatus comprising: (A) a holder; (B) a reference body having a reference surface that is identical in Z-position with a surface of a sample, the reference body being placed on or in the holder; (C) a probe-positioning device for bringing the probe into contact with the reference surface; (D) a controller for controlling motion of the probe-positioning device in a Z-direction; (E) position-measuring means for measuring a Z-coordinate of the probe at which the probe is in contact with the reference surface; (F) a memory for storing a positional coordinate outputted by the position-measuring means; and (G) probe contact detection means for detecting that the probe is in contact with the reference surface, wherein in order to bring the probe into contact with the surface of the sample, the probe-positioning device is moved until the Z-coordinate of the probe reaches the value stored in the memory.