Dynamic force microscopy in fluid

✍ Scribed by Lantz, M.; Liu, Y. Z.; Cui, X. D.; Tokumoto, H.; Lindsay, S. M.

• Publisher: John Wiley and Sons
• Year: 1999
• Tongue: English
• Weight: 214 KB
• Volume: 27
• Category: Article
• ISSN: 0142-2421
• DOI: 10.1002/(sici)1096-9918(199905/06)27:5/6<354::aid-sia541>3.0.co;2-4

✦ Synopsis

Low-amplitude dynamic force microscopy can operate in a non-contact mode, sensing changes in liquid properties near a surface. Operation of the microscope in water at the higher amplitudes often required for stable imaging has been investigated. When driven by direct application of a force to the tip, the microscope is stable over a wide range of operating frequencies. At low frequency, the interfacial sti †ness extracted from approach curves is found to be of the order of 1 N m-1 on Ðrst contact, which is indicative of imaging via a compressed liquid layer. Measurements of the spectral response of the cantilever and numerical simulations conÐrm this and show that viscous damping at the surface also plays a role.