3D Semicircular Flash Memory Cell: Novel Split-Gate Technology to Boost Bit Density

Three-dimensional (3D) semicircular split-gate flash memory cells have been successfully developed for the first time. Reduction of fringing field effects is essential to extract maximum performance from the split-gate cells, and careful design of Floating Gate (FG) cells achieves superior program slope and program/erase window at much smaller cell size relative to circular Charge Trap (CT) cells. It is projected that the semicircular split-gate FG cell is a promising candidate to realize more than four bits/cell (QLC) for significantly higher memory density at a lower number of stacking layers.