In an AFM, the microscope scans a sharp probe over the sample surface. This probe is a very sharp silicon tip, attached to a lever. The AFM uses the sharp probe to physically “feel” the shape of the surface, making sure the probe does not get damaged, often my tapping the surface. The tip movement is measured by bouncing light off the back of the lever and measuring the distance it moves.

Because the probe is very sharp, the resolution of this type of microscope can be very high. AFMs are small, light, and costs less to manufacture and purchase compared to other microscopes observing this range. It is also much more appropriate for use with samples that are not resistant to vacuum conditions.

What you end up with is a map of the surface, a picture of the highs and lows of the surface. You can tell a lot about the sample by looking at the surface For example Au nanoparticles here, we can look at the density and shape of the nanoparticle which will help us choose the right materials for the future.