Damage of functionalized self-assembly monomolecular layers applied to silicon microgear MEMS

Tooth surfaces of silicon-based MEMS microgears are described as smooth surfaces covered by adhesive asperities (nanoblocks). To reduce adhesive effects, the tooth surfaces are functionalized by OTS-SAM (Octadecyltrichlorosilane self-assembly monomolecular) carbon-based functionalized coatings. The wear of the coating is modelled using the modified Goryacheva-Torskaya model of damage accumulation. The amount of energy dissipated by different physical and chemical mechanisms along with energy dissipated by mechanical deformation of the counterparts is used to evaluate the frictional force. The main scenarios of wear process within the coating are described and discussed. The damage evolution is described for several levels of external load.