Depth sensing nanoindentation, mechanical properties

In this chapter, we overview basic techniques for making nanoscale adhesion and mechanical property measurements. Both quasi-static and dynamic measurements are addressed. In Section 2 of this chapter, we overview basic AFM instrumentation and techniques, while depth-sensing nanoindentation is overviewed in Section 3. Section 4 addresses recent advances in instrumentation and techniques... 

Depth-sensing nanoindentation is one of the primary tools for nanomechanical mechanical properties measurements. Major advantages to this technique over AFM include (1) simultaneous measurement of force and displacement (2) perpendicular tip-sample approach and (3) well-modeled mechanics for dynamic measurements. Also, the ability to quantitatively infer contact area during force-displacement measurements provides a very useful approach to explore adhesion mechanics and models. Disadvantages relative to AFM include lower force resolution, as well as far lower spatial resolution, both from the larger tip radii employed and a lack of sample positioning and imaging capabilities provided by piezoelectric scanners. 

Fang Z et al (2009) Mechanical properties of porous silicon by depth-sensing nanoindentation techniques. Thin Solid Films 517(9) 2930-2935... 

Experimental techniques most commonly used to probe the plastic properties of thin film materials involve direct tensile loading of either a freestanding film or a film deposited onto a deformable substrate material, microbeam bending of films on substrates, substrate curvature measurement or instrumented depth-sensing nanoindentation. Sahent features of these methods, as well as specific examples of the adaptation of these methods for the study of mechanical properties in thin films, are briefly addressed in the following subsections. 

Mechanical Properties Using Depth Sensing Nanoindentation... 

Depth sensing nanoindentation is a viable alternative to AFM beam bending for mechanical property measurements on polymer surfaces. The technique provides quantitative results owing to careful calibration of the system compliance and tip area/shape. It suffers from the high minimum load (about 1 iN) necessary for imaging prior to indenting. A new approach, which combines the best elements of both approaches, is still needed. 

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