TOWARDS MAGNETIC MICROACTUATION: PREPARATION OF Ni-Mn-Ga MICROPILLARS USING Xe PLASMA SOURCE FIB-SEM

摘要

The fast and large actuation strain together with the possibility of remote operation by magnetic field makes the magnetic shape memory (MSM) alloys promising candidate for actuation on microscale [I]. We considered fabrication of various micro-magneto-mechanical systems (MMMS) in analogy to micro-electro-mechanical systems (MEMS). For a research and rapid prototyping of microscale structures and actuators based on MSM alloys, the focussed ion beam (FIB) milling technique was used as one of the most advanced microstructure prototyping technologies. In top-down approach, the well-characterised macroscopic material is shaped into the microscopic devices. In our work we investigated the possibility of using Xe-ion beam milling for Ni-Mn-Ga MSM single crystals. The FIB milling was performed using fully integrated Xe plasma source FIB with scanning electron microscope (FIB-SEM) TESCAN FERA3 GM. The process was monitored by secondary electrons imaging (Everhart-Thornley SE detector). We fabricated basic pillar structures in various sizes with different ion beam conditions [2]. Examples of such micropillars are shown in Fig. 1.