Why is silicon nitride chosen for the tip material for the cantilevers for the contact mode AFM?
Simply saying, because silicon nitride is a generally used material in silicon IC process. • Is there any advantage in a silicon nitride tip? Yes. The silicon nitride tip is recommended for stable AFM measurement in contact mode, since silicon nitride tip is hard to wear compared with silicon tip (see right). Large tip force is loaded to a sample surface in contact mode AFM in air because of the contamination layers on the tip and the sample. This may cause tip wear, so harder material tip is preferable. • Does the silicon nitride tip give a good result for all samples? The silicon nitride tip works for most of samples. There are still some exceptions. If you measure a silicon nitride sample in contact mode AFM with the silicon nitride tip, sometimes AFM images are distorted. • Is there any treatment for changing a silicon nitride tip into hydrophilic? Try to expose the tip with UV light. Or, if you have a oxygen plasma reactor, try it. That is the way to change the tip surface in a sh
