Three-Dimensional Numerical Analysis of Switching Properties of High-Speed and Nonvolatile Nanoelectromechanical Memory

Abstract

Static and dynamic mechanical properties of the movable floating gate are investigated for a newly proposed highspeed and nonvolatile nanoelectromechanical memory, which features a buckled floating gate incorporating the nanocrystalline silicon quantum dots integrated onto the gate of a MOSFET. By conducting a 3D finite element simulation, we analyze the structural parameter dependence of the switching force F <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">s</sub> needed for the buckled floating gate to flip-flop between its bistable states and derive the relationship F <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">s</sub> infin L <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">-4</sup> T Z <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">0</sub> <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sup> where L, T, and Z <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">0</sub> represent the length, thickness, and equilibrium displacement of the buckled floating gate, respectively. We demonstrate that the switching frequency can be increased while maintaining the switching force when we downscale all the floating gate dimensions proportionally along with the scaling law. We also show that the switching voltage can be reduced down to less than 15 V while maintaining the ON/OFF operation range of the sense MOSFET by optimizing the cavity structure which sustains the inside buckled floating gate