Atomic force microscopy as a tool for multiphysics nanoscale characterization

Join Zoom Meeting: https://purdue-edu.zoom.us/j/93857631004

Abstract: An atomic force microscope (AFM) consists of a sharp cantilever mounted tip interacting with a sample. This microscope is capable of topographic imaging of samples down to atomic resolution. Additionally, the physical interactions between the tip and sample can be leveraged to investigate a variety of multiphysics problems. AFM can measure the nanomechanical elasticity, viscoelasticity, adhesion, and failure of nanoscale structures. It can map conductivity, surface potential, and piezoelectric response with nanoscale resolution. It can probe the distribution of chemical species on a surface. In this talk, I will highlight my past research efforts that have touched on characterizing these different physical properties with AFM. This includes studying the nanomechanical properties of cellulose with force-displacement curves, measuring the ferroelectric response of hafnium oxide thin films with piezoresponse force microscopy, and mapping the distribution of active shampoo ingredients on hair with atomic force microscopy mass spectrometry. These research efforts have focused on advancing AFM’s capabilities in performing these diverse types of measurements on very different samples.

Bio: Ryan Wagner is a Research Assistant Professor in the School of Mechanical engineering at Purdue University. He received his PhD from Purdue in 2014 and afterward took postdoctoral appointments at the National Institute of Standards and Technology and Asylum Research,  an AFM instrument manufacturing company. His research interests include nanotechnology, microscopy, interferometry, spectrometry, metrology, vibrations, and dynamics.