Is flash memory facing a physics crisis?
 

NAND is definitely going to slow down. There are some fundamental practical limits and some fundamental physics limits,' Harari said. 'We have three or four generations, five at most. Beyond that, we may need a different technology'.

The problem is that the different subcomponents inside these chips can't be shrunk much further. One layer, called a tunnel oxide, can probably be shrunk to about 80 angstroms. In other types of chips, this layer can be shrunk to 12 angstroms.

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