THREE-DIMENSIONAL MEMORY AND FABRICATION METHOD THEREOF

A method for fabricating a three-dimensional memory includes forming a first stack substrate on a substrate. The method also includes forming bottom select gate cuts through the first stack structure, and forming first sacrificial layers within the bottom select gate cuts. The method further includes forming a second stack structure covering the first sacrificial layers and the first stack structure. Both the first stack structure and the second stack structure include alternately stacked dielectric layers and gate sacrificial layers. The method further includes replacing the first sacrificial layers with first conductive layers, and replacing the gate sacrificial layers with gate conductive layers. The method further includes forming trenches exposing the first conductive layers on the side of the first stack structure far away from the second stack structure. The method further includes replacing the first conductive layers with insulating layers via the trenches.