Sub-300 Millivolt Operation in Nonvolatile 300 nm x 100 nm Phase Change Nanoelectromechanical Switch

This paper reports the design, fabrication, and characterization of the Fin Phase Change Nanoelectromechanical Relay (FinPCNR), a truly nanoscale switch. We harness the nonvolatile volume transformation of GeTe, a widely used phase change material, to drive the laterally actuating relay. The PCNR is turned ON by applying a sub-300 mV short actuation pulse (< 500 ns) to a fin-shaped heater (l: 300 nm, w: 100 nm, h> 100 nm). Novel nanofabrication techniques are developed to self-align multiple functional vertical layers on the heater sidewall. In the OFF state, we achieve near zero leakage (23 fA) by maintaining a sub-5 nm airgap between the metal channel and the drain/source electrodes. This device is an ideal candidate for high density, ultra low-leakage memory circuitry as it combines the nonvolatility of GeTe and the high ON-OFF current ratio of NanoElectroMechanical (NEM) relays.