Carnegie Mellon University

Micro and Nano Systems Laboratory

College of Engineering

Phase change NEMS relays

Mechanical relays use an air gap to control current flow, which can eliminate off-state leakage and offer better energy efficiency. A major bottleneck to the adoption of mechanical relays is the scalability of these devices to sizes that are comparable to state-of-the-art transistors. Our lab focuses on the development of the phase change NEMS relay (PCNR), a highly scalable mechanical relay based on the mechanical expansion of GeTe phase change material. The PCNR is non-volatile, meaning it can retain states without power and can be used as a memory. States are changed by converting the GeTe between room temperature stable crystalline and amorphous states which differ in volume by 10%.

Micro-Robotic Actuators

There are currently no complete micro-scale robotic systems with the ability to proficiently perform complex tasks. Our lab is working to develop small, high work density actuators that can be powered by on-robot energy sources and integrated with mechanisms to perform complex tasks. We explore the use of GeTe as a semiconductor material with one of the largest work densities for the making of micro/nanoscale actuators. The 10% volume change in GeTe between liquid and crystalline states is harnessed to deform micro-cantilevers. These cantilevers can then be integrated with various mechanisms to form complex motion.