Focused Ion Beam Fabricated Polystyrene-Platinum Thermal Microactuator

Abstract

Individually released polystyrene-platinum bimorph microcantilevers that have potential applications as MEMS/NEMS thermal actuators are produced using focused ion beam micromachining technique. The microcantilevers are sharply defined and triangular in cross-section, and are about 20µm long, 2 µm wide and 1.5 µm thick. The fabrication process is fast (< 3 hours) and does not require any mask or resist. The nanometer-scale displacement of the resulting bimorph microactuator with respect to temperature change is recorded via imaging in a scanning electron microscope, equipped with a heating stage. By increasing the temperature to ca. 55 °C, a tip deflection of ca. 380 nm was measured. This result is compared with the numerical result obtained from a finite element analysis (FEA).