Nanoelectromechanics of Piezoelectric Indentation and Applications to Scanning Probe Microcopies

随着压电力显微镜、原子力显微镜和超声力显微镜等纳米压痕和扫描探针显微镜技术的出现，使得在纳米尺度上探测材料的机电性能成为可能。这对于研究微电子机械系统、复合材料和复合氧化物(铁电体和压电体)以及生物材料至关重要。铁电材料在纳米机电系统中用作随机存取存储器。它们的实际实现需要能够在10 nm的长度尺度上定量地探测铁电体的性质。然而，扫描隧道显微镜技术在定量方面的缺乏阻碍了纳米机电性能定量成像的发展。要将机电扫描电子显微镜和纳米压痕技术推向定量表征工具，主要挑战仍然是各种尖端-表面连接的定量机电学--压电接触力学。他们研究中的研究人员正在解决这些问题。这些结果在长度尺度的层次上是相关的，从毫米(生物组织)到纳米(细胞级别的生物应用)。

Abstract 0509936With the advent of nanoindentation and scanning probe microscopy (SPM) techniques, such as piezoelectric force microscopy, atomic force acoustic microscopy and ultrasonic force microscopy, it has become possible to probe electromechanical properties of materials at the nanoscale. This is critical for the study of microelectromechanical systems, composites and complex oxides (ferroelectrics and piezoelectrics) as well as biomaterials. Ferroelectrics are used in nanoelectromechanical systems as random access memories. Their actual implementation requires the capability to quantitatively probe properties of ferroelectrics at 10nm length scale. However, the lack of quantitative aspects of SPM techniques hinders development of the quantitative imaging of nanoscale electromechanical properties. To propel electromechanical SPMs and nano-indentation techniques to a quantitative characterization tool, the main challenge remains quantitative electromechanics of various tip-surface junctions - the piezoelectric contact mechanics. The investigators in their study are addressing these problems. These results are relevant at hierarchy of length scales, from the millimeter (biological tissues) to the nanometer (bio-applications at the level of cells).