It’s pretty easy to go from talking about the earliest 24-layer 3D NAND to talking about the next-generation 32-layer 3D NAND, and then to progress through 48, 64, and more layers, but the amazing scale of a 96-layer part doesn’t really sink in when you just talk about numbers.
That’s why The Memory Guy was so charmed when Western Digital Corp. (WDC) invited me in for a briefing that gave me a more solid idea of how significant of a number 96 really is. The company brought along a plastic model that replicated the structure of its 96-layer BiCS NAND chip using clear plastic which was dramatically lighted from the inside.
WDC’s model was constructed using standard plastic sheeting, probably 1/8″ thick (~3mm), one sheet to represent the conductive polysilicon and one to represent the insulating silicon dioxide for each layer. Naturally, there are more than 96 layers in 96-layer NAND since there are source select transistors at the bottom and drain select transistors at the top. This adds a little bit to the layer count.
Another layer in the middle of Continue reading “96-Layer NAND in Perspective: WDC Video”
