US Patent 7637960 - Nanothin AFM cantilever

http://www.freepatentsonline.com/7637960.html

The spring constant of a micromechanical cantilever is in proportion to the cube of it's thickness. This patent from the University of Houston teaches a method of manufacturing ultrathin silicon cantilevers having a low spring constant to inspect soft specimens such as biomolecules. Claim 1 reads:

1. An AFM scanning probe comprising:

a) a cantilever; and

b) a tip integrally formed on the cantilever, wherein the tip extends in a substantially perpendicular direction to the longitudinal axis of the cantilever, and wherein the tip consists essentially of silicon, wherein the thickness of the cantilever is in the range of from about 100 to about 1000 nanometers.