SCANNING TUNNELING MICROSCOPE AND MEASURING METHOD THEREOF

Japanese Patent JPH05172509

A

PURPOSE:To shorten the time of measurement by switching a servo-scanning method and a save scanning method in response to the magnitude of the measuring range (or the measuring time) under the constant number of measuring points when the shape of the body surface to be detected, and performing the measurement. CONSTITUTION:The servo-control conditions required for a servo-scanning method is set Fl. Namely, a proportion controlling coefficient KP, an integration controlling coefficient KI and a differentiation controlling coefficient KD for a Z servo circuit for stabilizing a control system are inputted. Approach and save conditions required fox a save scanning method are set F2. Namely, the conditions such as saving positions and the distance between the measuring points and the parameters of the control system are imparted. Then, the measuring range (area) and the number of the measuring points in this range are set F3. The respective total measuring times T1 and T2 of the servo-scanning method and the save scanning method are computed based on the measuring area and the number of the measuring points. The magnitudes of T1 and T2 are compared. When T2>=T1, the servo-scanning method is selected. When T2