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having purchased a company called Matrix Semiconductor in 2006. Matrix developed a
means of stacking transistors one atop another to get to 8 or even 16 levels, multiplying
the amount of memory on a given size chip by the same number. There is a long way to
go with technologies like these!
4.11 Another Approach to Multilevel Cells
There is a completely different approach to storing multiple bits on a cell that is used
by fewer manufacturers but is quite possibly going to fi nd expanded use in the future.
This technology goes by different names, the most common being Saifun’s NROM,
Spansion’s MirrorBit, and its near-equivalent ...