AFM CAPABILITIES IN CHARACTERIZATION OF PARTICULATE MATTER: FROM ANGSTROMS TO MICRONS

摘要

Scanning Probe Microscopy has been successfully employed as surface characterization technique for more than 20 years. Atomic Force Microscopy is the most widely used subset of SPM, which can be used in ambient conditions with minimum sample preparation. AFM is capable to deliver unique three-dimensional topography information from angstrom level to micron scale with unprecedented resolution. This paper reviews most common methods of particle sample preparation for AFM evaluation. AFM is well suited for individual particle characterization. Standard set of measured parameters include: volume, height, size, shape, aspect ratio and particle surface morphology. With single-particle technique, physical parameters for each particle in a set can be recorded and the data set can be processed to generate a statistical distribution (i.e. ensemble-like information) for entire set of particles. Speeding up the process of obtaining data is critical for many reasons and definitely make AFM more attractive for individual particle imaging. In general AFM individual particle characterizations is both cost and time effective compare to electron microscopy. The resolution of AFM is greater or comparable to SEM/TEM. The main advantage of AFM for particle characterization is unambiguous morphology determination along with direct measurements of height, volume and 3D display.