Micro Electronic Mechanical Systems (MEMS)
Microelectromechanical systems (MEMS) consist of micron scale components which interact with their surrounding environment as sensors, actuators or both. Relative to macro scale systems, their large surface area to volume ratios increase the importance of electromagnetic and fluid dynamic effects. A multiphysics approach is therefore fundamental to the design of MEMS devices for which Xi have a proven experience in across physical domains and orders of scale.
The fabrication process for MEMS devices emerged from semiconductor techniques where thin layer deposition, photolithographic patterning and etch steps define the geometry. An understanding of how this process flow affects structural topology and device behaviour can be critical to the manufacturability of a device. Device reliability is a significant concern with stiction, thermal cycling, shock and vibration being modes which can often be mitigated through simulation. MEMS geometries often demand a fully coupled multiphysics approach with the sensitivity of mechanical structures to both viscous damping and electrostatic spring softening being two common examples.
Xi have design experience with both electrostatic and piezoelectric signal transduction, for mass market and bespoke industrial applications. COMSOL Multiphysics is our principal modelling tool and provides the ability to solve for a range of physical domains including structural mechanics, acoustics, fluid dynamics and electromagnetics. The use of shell or membrane elements to compute thin film mechanics, contact simulations for stress or stiction recovery analysis and fully-coupled electro-mechanics for pull-in and resonance extraction are some examples of MEMS concerns that Xi have extensive experience with.