Characterizing Metal-Insulator-Transition (MIT) Phase Change Materials (PCM) for RF and DC Micro-switching Elements

Metal-insulator transition (MIT) phase-change materials (PCM) are material compounds that have the ability to be either conductors or insulators depending on external stimuli. A micromachined test structure for applying external electric fields across MIT wire segments was designed and fabricated. Using this novel test structure, Germanium Telluride (GeTe) and Vanadium Oxide (VOx) were successfully transitioned from a conductor to an insulator. The resistivity of the GeTe wire segments increased three to five orders of magnitude with ∼40 V applied to the parallel plates of the test structure. The VOx wires exhibited an order of magnitude transition in resistivity with ∼20 V applied. Characterization of both RF and DC switching performance of these MIT wire segments was completed and GeTe and VOx appear to be viable materials for micro-switching.