Beyond Silicon

This article highlights that engineers are expanding their material world to reduce the cost and tailor performance of microdevices. Microelectromechanical systems evolved from the semiconductor industry, and silicon accounts for the vast majority of MEMS. This is not a surprise, since silicon lends itself well to semiconductor processing, and the designers and engineers of integrated circuits and MEMS understand the material’s characteristics and how to process it. Researchers at the University of California, Santa Barbara, meanwhile, are investigating the use of titanium as a wafer material for MEMS. Noel MacDonald, who heads the research group, said that titanium has advantages over silicon with regard to packaging, material properties, and the ability to create three-dimensional structures. Silicon is sure to be a material of choice among MEMS designers for a long time. But the availability of new materials, both for MEMS themselves and tooling to form microstructures, will open doors for new applications.