Patent ID: 6596992
Filing Date: 2003-07-22
Classification: G01Q,Y10S

Abstract:
A method of operating a scanning probe microscope having a cantilever having a minute probe at one end thereof and a reflective surface portion, a laser beam radiating device for radiating laser beans onto the reflective surface portion of the cantilever, an optical position sensor for detecting positions of laser beams reflected by the reflective surface portion, specimen moving means for moving a specimen relative to the probe, and cantilever oscillating means for periodically oscillating the cantilever at a predetermined amplitude, the method comprising the steps of:performing a first operation in which the specimen is moved relative to the probe and uneven surface data of the specimen surface is obtained when the optical position sensor detects a reduced amplitude of the cantilever smaller than the predetermined amplitude during the relative movement when the probe comes into contact with the specimen, the uneven surface data being obtained by controlling the specimen moving means to move the specimen relative to the probe in upward or downward directions in order to maintain the reduced amplitude constant; and performing a second operation in which physical action force data of the specimen is obtained by causing relative movement of the specimen and the probe while keeping the probe spaced by a predetermined distance from the specimen on the basis of the uneven surface data obtained in the first operation; wherein, in the first operation, the uneven surface data is obtained by controlling the oscillating means so that the cantilever is oscillated outside a frequency band defined by one-half the value of a dependent curve of the cantilever oscillating frequency and amplitude and, in the second operation, the cantilever is oscillated with a frequency near a resonant point of the dependent curve of the cantilever oscillating frequency and amplitude.