NAND can be tricky to manufacture, especially as the layer count increases. Manufacturers must maintain a reasonable aspect ratio with relatively high yields for the process to be economically feasible. The general trend is to add layers to help increase density, and when things become troublesome the die is split into multiple decks via string-stacking.
- Self-Aligned Double Patterning (SADP)
- Deposition, Etching, and Masking
- Layer Count
- Decks and String-Stacking
- CMOS, CMOS Under the Array (CUA), Wafer-on-Wafer (WOW)