Tribological evaluation of carbon coatings with and without nitrogen incorporation applicable to MicroElectroMechanical systems

Abstract

Although the integration into macro-devices and systems is a promising application, a MicroElectroMechanical system (MEMS) will become much more useful when it can be driven by a connected microactuator of small size, low-power and low-mass, and then controlled precisely at desired operation conditions. Recent demonstration of silicon material-based microactuator has revealed a profound influence of friction and wear on the whole performance including increased functioning, reliability, robustness, long life and high safety. Since undesirable tribological contacts occur directly between moving parts or moving and fixed ones and indirectly due to generated wear particles or dust particles interfering with tight tolerance, thin hard protective coatings, as an effective solution, which can be expected to reduce the friction and improve the wear resistance of silicon materials, need to be exploited. With the expected protective sputter-coatings of carbon with and without nitrogen incorporation, this work has been focused on the wear resistance improvement enhanced by nitrogen incorporation dynamically and initially evaluated from the view point of “wear particle generation”, in comparison to silicon materials for the possible use in MEMS. A discussion is also given into a new access to tribological evaluation of protective coatings applicable to MEMS.