Lubricated MEMS: effect of boundary slippage and texturing

Many types of micro-electro-mechanical-system (MEMS) based products are currently employed in a variety of applications. Recently, there has been an increase in the demand for higher reliability of MEMS which incorporate moving parts for each intended application. This is because the reliability of MEMS containing moving parts is poor and has a limited lifetime. Applying a lubricant to these systems to avoid wear hampers the movement due to the adhesive/surface forces, leading to stiction. By modifying the contacting surfaces, one is able to enhance the behavior of surfaces in a controlled way and thus alter the flow pattern in the liquid lubricating film for an enhanced performance. In this thesis, the concept of complex slip surface (CSS) as an artificial (deterministic) boundary slip surface is introduced. The thesis examines the exploitation of the artificial boundary slip to improve the performance of liquid lubricated-MEMS, with the emphasis on increasing the load support and reducing the coefficient of friction. Therefore, it is of great importance to get a clear view of the concept of the artificial boundary slip with respect to the performance of lubricated-MEMS.