Probing Physical Properties at the Nanoscale

Everyday devices ranging from computers and cell phones to the LEDs inside traffic lights exploit quantum mechanics and rely on precisely controlled structures and materials to function optimally. Indeed, the goal in device fabrication is to control the structure and composition of materials, often at the atomic scale, and thereby fine-tune their properties in the service of ever-more-sophisticated technology. Researchers have imaged the structures of materials at atomic scales for nearly half a century, often using electrons, x rays, or atoms on sharp tips (see the article by Tien Tsong in PHYSICS TODAY, March 2006, page 31). The ability to survey properties of the materials has proven more challenging. In recent years, however, advances in the development of scanning probe microscopy have allowed researchers not only to image a surface, but also to quantify its local characteristics— often with a resolution finer than 10 nm. We highlight several SPM techniques here, with an emphasis on those that address electronic and dielectric properties of materials and devices

High-resolution characterization of defects in oxide thin films

Nanometer sized defects in thin HfOx films are detected by atomic force microscopy facilitated leakage current measurements. Differences in the electrical properties of individual defects were distinguished. The effects of two mechanisms that localize the tip-sample interaction and increase spatial resolution were calculated. The expected increase in tip-sample current due to stress induced phase transformations and band gap narrowing has been calculated, and a behavior diagram is presented that shows the pressure necessary to generate a detectable current increase as a function of tip radius

Vibrations of the "beetle" scanning probe microscope: Identification of a new mode, generalized analysis, and characterization methodology

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Cantilever tilt compensation for variable-load atomic force microscopy

This material is presented to ensure timely dissemination of scholarly and technical work. Copyright and all rights therein are retained by authors or by other copyright holders. All persons copying this information are expected to adhere to the terms and constraints invoked by each author's copyright. In most cases, these works may not be reposted without the explicit permission of the copyright holder