Atomic Force Microscope Nanoscale Mechanical Mapping

The characterization of mechanical properties of materials has been an essential evaluation in the development of novel materials and devices. With ultra-sensitive force detection and spatial resolution at the nanoscale, atomic force microscopy proves an ideal tool to investigate the stress-strain relation of a material. Owing to the recent advances in the tip-sample interaction control and feedback scheme, in situ nanoscale mechanical property mapping on surface morphology is possible; its applications include the investigation of multiple-property changes for novel materials; especially for soft, biological, nanosized, 1D, or 2D materials. Although the AFM mechanical mapping techniques provide quantitative measurements, inconsistent testing protocols and the lack of conversion methods that allow AFM data to be linked and compared to other mechanical test values have stymied the use of AFM mechanical characterization. To resolve this problem, one has to understand the fundamental differences of AFM techniques as compared to the conventional mechanical tests. In this chapter, we look into the various aspects of AFM mechanical mapping techniques and propose a practical measurement protocol for a reliable quantitative measurement.