Electromechanical memory cell

Abstract

A low power, nonvolatile microelectromechanical memory cell stores data. This memory cell uses a pair of cantilevers, to store a bit of information. The on and off state of this mechanical latch is switched by using, for example, electrostatic forces applied sequentially on the two cantilevers. The cantilevers are partially overlapping. Changing the relative position of the cantilevers determines whether they are electrically conducting or not. One state represents a logical “1”. The other state represents a logical “0”. After a bit of data is written, the cantilevers are locked by mechanical forces inherent in the cantilevers and will not change state unless a sequential electrical writing signal is applied. The sequential nature of the required writing signal makes inadvertent or noise related data corruption highly unlikely. This MEMS memory cell can be implemented, for example, using a three-polysilicon-layer surface micro-machining process. The mechanical nature of the memory cell makes the cell immune to radiation. The cell is compatible with existing VLSI processes. Therefore monolithic memory devices comprising, for example, a plurality of the memory cells, read/write circuitry, and I/O circuitry, can be made using inexpensive, standard processes. The memory devices can be used in almost any electronic device requiring memory. For example the memory device is used in document processors, cell phones and satellites.