All engineering mumbo-jumbo aside, the resulting nanocone-tipped cells converted light-to-power with efficiency of 3.2% compared to 1.8% efficiency of conventional planarstructure of the same materials.
The planar cell structure integrated a Hi-K (high capacitance) metal gate stack into the NAND production to allow for smaller floating gates and thus higher storage capacity.
The 20nm 64Gb NAND uses a planar cell structure -- the first in the industry -- to overcome the inherent difficulties that accompany advanced process technology, enabling performance and reliability on par with the previous 25nm generation.