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Suigen, South Korea

Chung K.-H.,University of Ulsan | Lee Y.-H.,Park Systems Inc. | Kim H.-J.,Yonsei University | Kim D.-E.,Yonsei University
Tribology Letters | Year: 2013

Atomic force microscopy (AFM) is a key instrument in nanotechnology; however, AFM probe wear is a critical concern with AFM-based technologies. In this work, the wear progression of silicon AFM probes with different radii was thoroughly explored under various normal forces and sliding speeds. The results showed that the initial wear coefficient increased as the normal force increased. However, after a certain sliding distance, the wear coefficient was stable due to the flattening of the probe even with increasing normal force. It was also observed that the wear coefficient decreased with increasing probe radius and the wear of the probe increased as the sliding speed increased. From the overall results, it was concluded that the contact pressure plays a significant role in wear progression and may be responsible for a lower wear coefficient even with increasing adhesion forces due to wear. The wear rate was found to have an exponential dependence on contact stress, as proposed in recent literatures. © 2013 Springer Science+Business Media New York.

Park Systems Corporation | Date: 2014-04-02

The present invention relates to a leveling apparatus that levels an object to be leveled with a surface of a substrate by measuring the force applied to the object, and an atomic force microscope including the leveling apparatus. A leveling apparatus according to the present invention, which levels an object with a substrate such that one side of the object is brought in parallel contact with the surface of the substrate, includes: force sensors disposed to measure force at at least three points on the other side of the object; an angle adjusting unit disposed to adjust the angle between the object and the surface of the substrate; and a controller connecting with the force sensors and the angle adjusting unit to drive the angle adjusting unit on the basis of data from the force sensors. The controller obtains the data on force applied to the force sensors by bringing one side of the object in contact with the surface of the substrate at a predetermined angle, calculates the degree of relative inclination between the object and the surface of the substrate from the data on force, and levels the object with the surface of the substrate by adjusting the angle of the object or the substrate with the angle adjusting unit on the basis of the degree of relative inclination.

PARK SYSTEMS Corporation | Date: 2014-06-26

An image acquiring method for acquiring an image using a measurement apparatus including an image acquiring means which acquires an image of a surface of a target to be measured in the unit of predetermined size pixels and a moving means capable of moving the target to be measured, the image acquiring method includes: acquiring an image of a first region from the surface of the target to be measured through the image acquiring means; acquiring an image of a second region, which is different from the first region, by moving the target to be measured, through the moving means; acquiring a differential image by subtracting, from either the image of the first region or the image of the second region, the other image; and overlapping the differential image multiple times.

A scanning probe microscope images a surface of a sample by scanning the sample along a forward path while collecting data for imaging the surface of the sample, recording an uppermost position of the probe while the sample is scanning along the forward path, and scanning the sample along a return path while the probe is positioned higher than the uppermost position of the probe. The return scanning speed is configured to be higher than the forward scanning speed so that the surface image can be obtained rapidly. Also, the return path tracks the forward path until the beginning of the forward path is reached. In this manner, positioning errors caused by hysteresis in the scanning system can be eliminated.

Usukura J.,EcoTopia Science Institute | Usukura J.,Nagoya University | Yoshimura A.,Kyoto University | Minakata S.,Nagoya University | And 4 more authors.
Journal of Electron Microscopy | Year: 2012

Atomic force microscopy (AFM) combined with unroofing techniques enabled clear imaging of the intracellular cytoskeleton and the cytoplasmic surface of the cell membrane under aqueous condition. Many actin filaments were found to form a complex meshwork on the cytoplasmic surface of the membrane, as observed in freeze-etching electron microscopy. Characteristic periodic striations of about 5 nm formed by the assembly of G-actin were detected along actin filaments at higher magnification. Actin filaments aggregated and dispersed at several points, thereby dividing the cytoplasmic surface of the membrane into several large domains. Microtubules were also easily detected and were often tethered to the membrane surface by fine filaments. Furthermore, clathrin coats on the membrane were clearly visualized for the first time in water by AFM. Although the resolution of these images is lower than electron micrographs of freeze-etched samples processed similarly, the measurement capabilities of the AFM in a more biologically relevant conditions demonstrate that it is an important tool for imaging intracellular structures and cell surfaces in the native, aqueous state. © 2012 The Author. Published by Oxford University Press [on behalf of Japanese Society of Microscopy]. All rights reserved.

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