Patent ID: 7921466
Filing Date: 2011-04-05
Classification: G01Q

Abstract:
1. A method of use of an atomic force microscope by means of amplitude modulation, of the type that comprises exciting a natural vibration mode of a microlever (M) of said microscope, arranged on a sample to examine, and analyzing at least the variation in amplitude (A i ) of oscillation of an output signal (A i cos(ω i t−φ i )), where t is the time and ω i is the frequency of the microlever (M), representing the response of the microlever (M) to that excitation, in order to obtain topographical information on that sample, wherein said method further comprises an additional excitation of at least one other natural vibration mode of the microlever (M) such that at least two of said excitations of said natural vibration modes of the microlever (M) are carried out simultaneously, and analyzing at least the variation in phase (φ i ) of an output signal (A i cos(ω i t−φ i )) representing the response of the microlever (M) to said additional excitation, in order to obtain compositional information on said sample is carried out by means of an excitation signal (F i cosω i t) of higher frequency than the frequency of an excitation signal (F i cosω i t) used for obtaining said topographical information.