| 摘要 |
A memory string is configured by a plurality of memory transistors and a spare memory transistor connected in series. Word lines are connected to gates of the memory transistors. A spare word line is connected to a gate of the spare memory transistor. The memory string comprises a first semiconductor layer, a charge storage layer, a plurality of first conductive layers, and a second conductive layer. The first semiconductor layer extends in a perpendicular direction with respect to a substrate. The charge storage layer surrounds a side surface of the first semiconductor layer. The plurality of first conductive layers surround a side surface of the first semiconductor layer with the charge storage layer interposed therebetween, and function as the word lines. The second conductive layer surrounds a side surface of the first semiconductor layer with the charge storage layer interposed therebetween, and functions as the spare word line. |
