Nanostethoscopy: A new mode of operation of the atomic force microscope

摘要

The authors introduce a new mode of operation of the atomic force microscope (AFM). This detection scheme, a Nano-Stethoscope, involves using the atomic force microscope in a novel acoustic mode not generally recognized. The Nano-Stethoscope uses the conventional scanning feature to locate a desired site, positions the AFM microscope tip over the site, holds the cantilever stationary (in x and v) and records the tip's z-motion as a function of time. The tip/cantilever system thus functions as a micro-motion detector to respond to characteristic (open quotes)pulsations(close quotes), nano-configurational chances, or any other event that influences the position of the tip as a function of time. The authors have demonstrated the feasibility of using the tip of an AFM in this manner in a biological system with a measurement of the vibrations of an emerging shrimp egg nauplius ((approximately)3 (mu)m. -10 Hz) and on the Angstrom scale in a non-biological system i.e.. the thermal expansion of metal interconnect lines on a microelectronic circuit.