Multi-Bit Nano-Electromechanical Nonvolatile Memory Cells (Zigzag T Cells) for the Suppression of Bit-to-Bit Interference.

Multi-bit nano-electromechanical (NEM) nonvolatile memory cells such as T cells were proposed for higher memory density. However, they suffered from bit-to-bit interference (BI). In order to suppress BI without sacrificing cell size, this paper proposes zigzag T cell structures. The BI suppression of the proposed zigzag T cell is verified by finite-element modeling (FEM). Based on the FEM results, the design of zigzag T cells is optimized.

Scale effects on stiction-induced release voltage shift of nano-electromechanical (NEM) memory cells.

In order to overcome the limits of conventional flash memory, nonvolatile nano-electromechanical (NEM) memory has been proposed. The release voltage shift of a NEM memory cell induced by beam stiction has been studied by using one-dimensional analytical model and three-dimensional finite element analysis (FEA) simulation. As the size of a NEM memory cell decreases, stiction effects become more severe because the spring force becomes weaker. The influence of NEM memory cell scaling on release voltage shift has been discussed. If all geometrical dimensions are scaled in proportion, which is called general scaling, release voltage shift becomes larger, and release voltage becomes smaller. Then, if release voltage shift becomes larger than release voltage as general scaling continues, NEM memory cells do not work due to the permanently pulled-in cantilever beam. In order to prevent this, it is necessary to reduce beam length aggressively compared with other dimension scaling or to introduce more elastic and less adhesive beam material than existing beam material.