| Near-field scanning acoustic microscopy (NSAM) is a recent addition to the developing field of scanning probe microscopy. Its historical roots are scanning acoustic microscopy (SAM) first demonstrated in 1973 and scanning tunneling microscopy (STM), introduced in 1981. The NSAM uses acoustic waves to probe the sample but unlike the SAM that operates in the far-field regime, the resolution of the NSAM is not bound by the diffraction-limited spot created by an acoustic lens. Instead of an acoustic lens, the NSAM uses a sharp probe like those used in STM to contain the acoustic waves and deliver them to a spot of sub-wavelength dimension on the sample. While similarities in instrumentation exist between the NSAM and the STM, the contrast mechanism for the NSAM is based on variations in the acoustic properties of the sample in addition to surface topography.;The NSAM presented in this dissertation utilizes key components which are microfabricated using manufacturing processes similar to those used in integrated circuit fabrication. The microfabricated probes are comprised of silicon cones, with height on the order of 100 ;In addition to the topic of NSAM, some microfabrication technologies for STM and atomic force microscopy (AFM) are also described in this dissertation. |
