Skipping 128-layer does allow Micron some cost advantages, he said, but it's spending money to transition from floating gate to its charge trap RG architecture. "They have to invest in that transition." Micron's 3D replacement-gate NAND flash storage creates a cell-to-cell approach that is closer to an interaction-free structure that uses a nonconductive layer of silicon nitride acting as a NANO storage cell to trap electrical charges. (Image source: Micron)