Nanoindenting is a new method for characterization of material mechanical properties on a very small scale. Features less than 100 nm across and thin films less than 5 nm thick can be evaluated. Test methods include indentation for comparative and quantitative hardness measurements and scratching for evaluation of wear resistance and thin film adhesion.

Nanoindenting is performed in conjunction with atomic force microscopy (AFM). The area for testing is located by AFM imaging, and indentations and scratching marks are imaged by AFM after testing. A three-sided, pyramid-shaped diamond probe tip is used for imaging the sample and indenting or scratching. For indenting, the probe is forced into the surface at a selected rate and to a selected maximum force. For scratching, the probe is dragged across the sample surface while controlling the force, rate, length, and angles. Imaging is performed using the same probe for intermittent contact (tapping mode) AFM. The depth of indentations are measured from the AFM image after testing to evaluate hardness. A force-displacement curve obtained during indenting also provides indications of mechanical properties.

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Nanoindentation - Indentations from forces ranging from 1 to more than 100µN can be made to measure material hardness. Indentation depth or area is inversely proportional to hardness. Force displacement curves obtained during indenting indicate elastic modulus properties.

Scratching - Scribed patterns in the sample surface show potential for spalling or delamination of thin films.

Wear Testing - The diamond probe tip is repeatedly raster-scanned over the sample surface at a selected force. Wear durability is measured as a function of material loss from the tested surface. Depth of material loss is measured by AFM imaging after testing.

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• Hardness measurements for submicron-size features
• Thin film adhesion evaluations
• Coating wear durability
• Elastic modulus comparisons for thin films

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