Shape behavior analysis of a PMN-PT [001] actuated MOEMS micro-mirror

This paper presents how a Lead Magnesium Niobate - Lead Titanate (PMN-PT) based actuator, poled and cut along the [001] crystalline direction, can be used as an integrated actuator in a Micro Opto Electro Mechanical System (MOEMS). This cut was chosen as it has been proved to present piezoelectric coefficients that surpass 4500pm/V. This makes PMN-PT suitable for bulk usage. The actuator may be used as part of a Reconfigurable Free Space - Micro Optical Bench (RFS-MOB) to control the displacement of a micro-mirror. Finite Element simulations were used to study the influence of the actuator shape over the generated displacement, as well as the soldering medium. It was observed that for actuators with surfaces between 500×500μm² and 800×800μm² and a thickness of 200μm, displacement of up to 370nm is achievable. While the actuator profile impacts directly on the free surface shape it is also in direct correlation with the size of the usable area of the micro-mirror.