Controlled monolayer self-assembly process based on the atomic force microscopy nanoscratching method

The atomic force microscopy (AFM)-based mechanical nanoscratching method is employed to be integrated with self-assembly process on the surface of silicon (111) forming a novel fabricating approach: An AFM diamond tip is used to scratch the sample surface, forming complex structures with dimensions of several microns. Then the same sample is immersed into the hexadecane solution and heated to 200 °C for about 2 h. Finally, self-assembly monolayer is formed on all sample surfaces except the scratched area. Results of x-ray photoelectron spectroscopy analysis verify the formation of monolayer on the silicon surface. Mechanical properties of the sample such as friction and adhesive behaviours are studied by AFM. Results show that the scratched silicon surface has a larger friction force and adhesion force than the self-assembly monolayer area.