Atomic force microscopy at ultrasonic frequencies

We present a new type of near-field Acoustic Microscopy combining Atomic Force Microscopy (AFM) and Acoustic Microscopy. The lateral resolution is given by the probe diameter instead of the acoustic wavelength and can reach atomic scale on flat samples. The ultrasonic vibrations of the AFM cantilever are examined as well as the nonlinear interaction between the AFM tip and the sample surface. An ultrasonic image taken with the new technique is shown.