High Resolution, Near-Field Scanning Probe Acoustic Microscopy with Low Frequency and its Applications to Ferroelectrics and Other Related Materials

摘要

Low-frequency (below 100 kHz, even down to several kHz) near-field scanning probe acoustic microscopy (SPAM) was successfully developed based on the commercial atomic force microscope, providing a subsurface depth profile information and as well as nanoscale spatial resolution up to several run. SPAM was successfully used to image locally domain configurations of ferroelectric materials and subsurface structures of other materials (like amorphous films, etc.) Ferroelectric domain structures and the buried structures were clearly visualized by scanning probe acoustic microscopy. The acoustic imaging origin is discussed in terms of interaction between the excited acoustic wave and local structures beneath the SPAM tip. It is expected that the scanning probe acoustic microscopy in application to ferroelectrics and other materials undoubtedly enrich our understanding the nature of ferroelectricity and elasticity at submicro-, even nano-meter scale.