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报告内容摘要：
Within 4 years of the invention of the AFM, micro-fabricated cantilevers with integrated tips appeared, saving early practitioners from the joys of hand-assembling their cantilevers. However, even though many researchers soon understood the benefits of further miniaturization of the lever, standard commercial levers remained at the same 100 to 300 ?m size for nearly the next two decades, in part because making a commercial instrument capable of using much smaller levers presented significant technical challenges. Within the past few years, commercial instruments like the Cypher AFM have appeared which are capable of using cantilevers as small as 10 ?m in length and with resonance frequencies 5 MHz and higher and those levers are now readily available. Small levers bring two major benefits to AFM. The first is much smaller thermal noise, enabling quieter force measurements and higher resolution imaging with Angstrom-scale cantilever amplitudes. The second is a major speed boost for AC modes (tapping, non-contact) in both air and liquid. When coupled with other instrumental improvements such as a high-speed scanner, the shorter levers allow scanning with good tracking at rates 20X to 40X what was possible with conventional levers. I will talk about the technical details behind both these improvements. I will also present images and movies highlighting the improvements, including images showing individual vacancy defects on crystals and movies showing fast scanning on polymers, crystals, and biological samples.

报告人简介：
Dr. Cleveland has over 21 years of AFM experience, specializing in the physics of AFM. He has over 30 published papers, has been an invited speaker at many prestigious AFM/SPM conferences, and is a co-inventor on numerous patents. Previously, he was a Research Scientist at Digital Instruments. He received his PhD from UCSB and MS from University of Minnesota.