A processing method uses a probe of a scanning probe microscope. A fine
marker is formed in a processing material by thrusting the probe, which
is made of a material harder than the processing material, into a portion
of the processing material disposed in the vicinity of an area of the
processing material to be processed by the probe during a processing
operation. A position of the fine marker on the processing material is
detected during the processing operation. A drift amount of the area of
the processing material is calculated in accordance with the detected
position of the fine marker. A position of the area of the processing
material is corrected in accordance with the calculated drift amount.