Electro-Thermally Actuated Non-Volatile Mechanical Memory With CMOS-Level Operation Voltage and Low Contact Resistance

A non-volatile mechanical memory device with CMOS-level operation voltage and low contact resistance is proposed utilizing electro-thermal actuation method for the first time. Unlike the most widely used electrostatic actuation method in microelectromechanical systems (MEMS) devices, electro-thermal actuation is known to produce large actuation force and displacement with low operation voltage, which are preferable attributes of a mechanical memory. In addition, stiction, one of the most notable failure mechanisms of MEMS devices referring to the inadvertent permanent adhesion between two surfaces, can be exploited to significantly improve the energy efficiency of mechanical memory by retaining the ON-state without power. We devised a non-volatile mechanical memory device capable of performing multiple cycles of write and erase operations with CMOS-level voltage by utilizing electro-thermal actuation and stiction. The fabricated electro-thermally actuated mechanical memory successfully performed 200 repeated cycles of write and erase operations at 0.9V and 1.0V, respectively. Thanks to the high contact force generated by electro-thermal actuation, the fabricated device achieved the contact resistance of 17 \boldsymbol {\Omega } . Lastly, we confirmed that the fabricated device successfully retained both ON and OFF states upon removal of power beyond 10 6 seconds. [2021-0178]