Semiconductor structure and its fabrication method, memory and memory system

Abstract

A fabrication method of a semiconductor structure includes forming a stack structure and a memory channel structure on a substrate. The memory channel structure penetrates through the stack structure along a stack direction and extends into the substrate to form an extension part. The memory channel structure includes a memory function layer and a channel layer. The method further includes removing the substrate and exposing the extension part, and forming a sacrificial layer on a side of the stack structure where the substrate is removed from. The sacrificial layer wraps a part of the exposed extension part. The method also includes removing the memory function layer in the unwrapped extension part and exposing the corresponding channel layer, removing the sacrificial layer, exposing the remaining memory function layer in the extension part, and forming a semiconductor layer on a side of the stack structure where the sacrificial layer is removed from.