Development of a Variable Temperature Near-field Scanning Acoustic Microscope with Rapid Sample Access

University Of Virginia Main Campus, Charlottesville VA

Investigators

Abstract

This award from the Instrumentation for Materials Research program will enable the University of Virginia to develop a variable temperature near field scanning acoustic microscope to map elastic properties on a nanometer scale on solids of interest to physics, chemistry, materials science, biology and engineering and to enhance teaching in the physics undergraduate laboratory. The microscope will use custom designed scanning heads with integrated cantilever sensors capable of operation at low temperatures and interfaced to existing control electronics. A low vibration refrigerator of the pulse tube type (which has no moving parts) will be acquired and used to cool the scanning head. The choice of the pulse tube refrigerator (which operate in any physical orientation) enables the positioning of the scanning head on top facilitating rapid sample access. The integrated cantilever sensing scheme will simplify the future marriage of the microscope to other instruments such as electron microscopes. It will also enable study of biological samples and solid liquid interfaces where optical detection schemes do not work.. The integrated detection scheme should also be attractive to emerging industrial microelectronics where rapid nanometer scale flaw detection is desired. This award from the Instrumentation for Materials Research program, the University of Virginia will develop a new microscope using high frequency sound waves and operating over a wide temperature range to map elastic features on a nanometer length scale in solid state materials of interest to physics, materials science, biology and engineering as well as to enhance teaching in the physics undergraduate laboratory. The microscope will be of the scanning type and images will be obtained digitally. The acoustic sensor for the microscope will be fabricated using integrated microelectronic technologies. This integrated sensor scheme simplifies the future marriage of the proposed microscope to other instruments such as electron microscopes. It will also enable the imaging of biological samples and solid liquid interfaces with resolution better than that obtained optically. The development of this new scanning acoustic microscope will benefit the study of crystalline and non-crystalline solids and will have a wide ranging impact including in the area of emerging microelectronic processes where rapid nanometer scale flaw detection is desired.