Imaging MEMS motion at nanoscale with time-resolved scanning electron microscopy  

Session

Poster Session One

Authors

PhD student Mohamed Zaghloul (2), PhD student Abbas Kosari Mehr (2), Prof.dr Riccardo Bertacco (2), PhD student Simone Cuccurullo (2), Dr Federico Maspero (2), PhD student Hao Chen (2), Associate Professor Aldo Ghisi (2), Prof.Dr Alberto Corigliano (2), Dr Silvia Maria Pietralunga (1), Associate Professor Alberto Tagliaferri (2), PhD student Giulia Pavese (2)

Affiliations

1. National Research Council (CNR
2. Politecnico di Milano

Keywords

Micro Electro-Mechanical System; time-resolved scanning electron microscopy; optical MEMS, in-plane MEMS

Abstract text

Reconfigurable micro-optics and on-chip integrated photonics often rely on micro-opto-electro-mechanical-systems to provide dynamical optical processing such as beam steering and focusing or optical coupling and phase tuning. In designing and fabricating micro-electro-mechanical systems (MEMS), and assessing their quality, a local and direct measurement of their motion on a point-by-point basis is quite useful. Such a technique must be fast enough to track the MEMS dynamics with sub-micron resolution. In this work, we introduce and discuss an implementation of dynamical imaging of MEMS by time-resolved scanning electron microscopy (SEM). MEMS resonators are actuated close to their resonance frequencies, and we show how to obtain stroboscopic movies by a proper sequential acquisition of secondary electron signal. Unprecedented information about local trajectory the provided, the microsecond scale and at tens of nanometer lateral scale. In-operand nonlinearities in the response of the system, interpretable as related to system hardening are brought into evidence. We also discuss strategies to reach the ultrafast time scale.