As others here have pointed out -- you don't need to do lithography 300 times. The big breakthrough of 3D NAND is depositing alternating layers of films to bui

As others here have pointed out -- you don't need to do lithography 300 times. The big breakthrough of 3D NAND is depositing alternating layers of films to build most of the layers. This is 3 stacks of >100 layers.