US Patent 11792989 Word line structure of three-dimensional memory device

Methods and structures of a three-dimensional memory device are disclosed. In an example, the memory device comprises a substrate, a stack structure on the substrate, and at least one gate line slit extending along a first direction substantially parallel to a top surface of the substrate, and dividing the stack structure into at least two portions. The stack structure includes at least one connection portion that divides the at least one gate line slit, and conductively connects the at least two portions.