Professor Bryan D. Huey
University of Connecticut
Friday, March 6
11:00 a.m.
Room 214 S. W. Mudd
Nanoscale and New Nano-Volumetric Materials Property Mapping
Atomic Force Microscopy has been a ubiquitous tool for nanotechnology since its invention 30 years ago, primarily to map the topography and local properties of materials surfaces. At UConn and elsewhere, substantial developments advanced high speed imaging as well, especially for investigating materials dynamics and bridging the eras of “Combinatorial” and “Big Data” science. However, sub-surface nano- and meso- scale features can be just as crucial to the macroscopic performance and reliability of real-world materials applications. Accordingly, we are developing Tomographic AFM to provide unprecedented insight into materials behavior throughout the thickness of an expanding range of specimens. Examples include 3-Dimensional maps of current networks in working solar cells, piezoelectric properties as a function of thickness for multilayer coatings, stiffness maps of human teeth, and ferroelectric domain patterns throughout multifunctional thin films and composites. Voxel dimensions as fine as 25 nm3 are achieved, and unit-cell-thickness depth resolution has been demonstrated. Aside from literally a new perspective, unexpected behavior is also sometimes revealed beneath the surface, such as the beneficial photoactivity of planar defects in CdTe solar cells, inverted relative photoconductivities for grain boundaries in MAPbI3 films, and emergent ferroelectric domain patterns and properties in superlattices. Such novel insight into nanoscale volumetric materials properties is sure to advance fundamental and applied materials science and engineering as Tomographic AFM transforms the way we look at, and beneath, surfaces.
