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Scanning Probe Microscopy (SPM) generally refers to a set of surface characterization techniques that utilize micro-machined cantilever probes with sharp tips to scan the sample surface. Since its inception in the 1980s, SPM has evolved into one of the most powerful tools for nanoscale measurement and imaging. High resolution topographical surface characterization is perhaps the most common use of the SPM, but a wide range of advanced SPM modes are also available to study the electrical, magnetic, and mechanical properties of surfaces.

Traditionally, most Atomic Force Microscopes use a laser beam deflection system where a laser is reflected from the back of the reflective AFM lever and onto a position-sensitive detector. AFM tips and cantilevers are typically micro-fabricated from Si or Si3N4. Typical tip radius is from a few to 10s of nm.

Analogous to how an Scanning Tunneling Microscope works, a sharp tip is raster-scanned over a surface using a feedback loop to adjust parameters needed to image a surface. Unlike Scanning Tunneling Microscopes, the Atomic Force Microscope does not need a conducting sample. Instead of using the quantum mechanical effect of tunneling, atomic forces are used to map the tip-sample interaction. Often referred to as scanning probe microscopy (SPM), there are Atomic Force Microscopy techniques for almost any measurable force interaction – van der Waals, electrical, magnetic, thermal. For some of the more specialized techniques, modified tips and software adjustments are needed. In addition to Angstrom-level positioning and feedback loop control, there are 2 components typically included in Atomic Force Microscopy: Deflection and Force Measurement.