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Product Briefing Outline: Veeco Instruments has introduced the ‘HarmoniX’, a powerful new atomic force microscope (AFM) technique for high-resolution nanoscale imaging and analysis. Veeco’s HarmoniX Nanoscale Material Property Mapping enables AFM users to simultaneously, and in real-time, acquire high-resolution images as well as high-resolution, quantitative material property maps. This technique is effective for characterization of soft materials, thin films, small particles, or domains within a bulk solid.

Problem: HarmoniX enables highpixel-density material property mapping at real-time, and at regular SPM imaging speeds. The alternative technique of force volume, which is typically operated at approximately 1 curve/second, would take several days to acquire a 512 x 512 pixel image. HarmoniX imaging can acquire a material map of this size in about 15 minutes, but unlike the force volume technique, HarmoniX delivers high-resolution images. An additional benefit of the HarmoniX technique is that the force curve data are automatically, and immediately, analyzed to provide real-time image data directly, and simultaneously provides maps of properties such as adhesion, stiffness and dissipation. No additional processing is required to extract these quantities and no rescanning of the same region is required to obtain different properties.

Solution: HarmoniX material mapping is able to deliver the full spectrum of quantitative results through the advanced design of the HarmoniX probes. This unique design, which offsets the probe tip from the cantilever, enhances the signal-to-noise ratio of the cantilever harmonics in ‘TappingMode’ by coupling the normal forces of the tip with the torsional, or “twisting” motion of the cantilever. It is the combination of full-spectrum multiple harmonics from both the flexural and torsional motion of the cantilever that enables the change to AFM material mapping, providing force distance curves — the basis for quantitative material property mapping. Since HarmoniX is based on the TappingMode technique, it is able to limit deformation depths to as little as 1 nanometer while using extremely sharp SPM probes. Deformation depth is proportional to contact area, which in turn is proportional to lateral resolution, and this is how it provides material mapping at SPM resolution.

Applications: Nanoscale quantitative material property mapping of adhesion, stiffness, dissipation, peak force, and average force for a wide range of materials.

Platform: The HarmoniX mode is now available on all Veeco scanning probe microscopes that are powered by the new NanoScope V controller, including the MultiMode V, DimensionTM V, and BioScopeTM II.

Availability: June 2008 onwards.