Dynamic mode AFM of polished sapphire

For some applications, sapphire or glass surfaces need to be polished down to sub-nanometer roughness. The images obtained here show polishing marks in and small contamination particles on the surface.

Image of polished sapphire

Image was recorded in dynamic mode. System: NaniteAFM with 10µm scan range connected to a C3000 controller Cantilever: NCLAuD (Nanosensors) Image processing: Nanosurf Report software Sa = 0.12nm
The particles on the surface cause large values for the skewness and kurtosis of 49 and 2770, respectively.

Profile showing the depth of scratches

The profile shows the sub-nanometer depth from the polishing marks. The profile was generated with Gwyddion software, taking the average of 4 adjacent pixels.