ABSTRACT
Atomic force microscopy (AFM) enables the measurement, graphical representation, and control of materials on the surface and immediate subsurface layers of electrical conductors, semiconductors, and insulators. These surfaces can be measured in air and other gases, in transparent liquids, or in vacuum, with temperature control. As opposed to most electron microscopy methods, AFM routinely enables nanometer-scale characterization and measurement, without the requirement for placing the sample in a vacuum. Some AFM systems with low levels of electrical, mechanical, and optical noise even allow for atomic-scale characterization of materials, usually when the sample presents an atomically flat surface to the AFM probe. The AFM also enables nonimaging methods to examine sample surface and immediate subsurfaces by using a collection of techniques generally called spectroscopic techniques. In these techniques, the AFM probe may not necessarily raster scan the sample surface, but rather, it collects the information about the sample by varying a parameter while the AFM probe stays at a fixed in-plane (XY) position above the sample surface. These parameters include probe?sample distance and the electrical potential difference between the probe and the sample. Applications to the measurement and characterization of microsystem components are illustrated in several case studies.
