A semiconductor memory includes a substrate, a source line layer above the substrate in a memory region and a peripheral region of the substrate, a first insulating layer above the source line layer, a first conductive layer on the first insulating layer in the memory and peripheral regions, an alternating stack of a plurality of second insulating layers and a plurality of second conductive layers on the first conductive layer in the memory region, and a plurality of pillars extending through the alternating stack of the second insulating layers and the second conductive layers, the first conductive layer, and the first insulating layer in the memory region. A bottom end of each of the pillars is in the source line layer in a thickness direction. A carrier density of the source line layer is higher in the memory region than in the peripheral region.