Ferromagnetic Shape Memory Actuator for Large 2D Optical Scanning

This paper reports on the design, fabrication and performance of a ferromagnetic shape memory alloy (FSMA) thin film actuator for two degrees of freedom (2D) control of a bulk micromirror. The actuation mechanism is based on a simultaneous ferromagnetic and martensitic transformation. A monolithic actuator design has been developed with two thermally and magnetically decoupled actuation units. The problem of FSMA thin film integration is solved by a novel transfer bonding process. First demonstrators of the FSMA actuator show a highly nonlinear response at low actuation voltage allowing large optical scanning angles up to 65 ° at tunable frequencies.