Characterization of MEMS Devices for the Study of Superfluid Helium Films*

Measurements on the mechanical attributes of MEMS resonators were performed at room and low temperatures. Specially devised resonators which can be actuated for shear motion were designed and fabricated using a state-of the-art multi-user MEMS process. The devices consist of a pair of parallel plates with a well-defined gap whose size can be controlled with high accuracy down to the sub-micron range. A full study of resonance properties at various pressures was performed at room temperature. Details of design, fabrication, and operation will be presented along with results from a preliminary study of a resonator immersed in liquid $^{4}$He. The devices show potential for use in low temperature experiments and to investigate novel phenomena in quantum fluids at the micro/nano scale such as superfluid $^{3}$He films.