90-nm-node multi-level AG-AND type flash memory with cell size of true 2 F²/bit and programming throughput of 10 MB/s

The first true 2-F²/bit flash cell with a programming throughput of 10 MB/s was developed. In this cell, diffusion-layer local bit lines of an assist-gate AND-type flash are replaced by inversion-layer ones under assist gates. The bit-line pitch is thus reduced to 2 F. A drain-disturbance-free and soft-write-free flash cell was produced by means of a new diffusion-layer-less technology. Source-side injection programming is applicable to the new flash cell; therefore, the cell programming time is reduced to 1 μs. The smallest memory cell (0.0162 μm²/bit) achieved to date was accomplished by using a 90-nm technology node and applying multi-level cell technology.