Three-dimensional memory device with support structures in gate line slits and methods for forming the same

Abstract

A three-dimensional (3D) memory device includes a memory stack including interleaved a plurality of conductor layers and a plurality of insulating layers extending laterally in the memory stack, a memory block including a plurality of channel structures extending vertically through the memory stack, a plurality of source structures extending vertically and laterally in the memory stack and being in contact with the memory block, and a plurality of conductor portions and a plurality of insulating portions being interleaved and locating between two adjacent source structures along a direction which the source structure extends. The interleaved plurality of conductor portions and plurality of insulating portions are each in contact with corresponding conductor layers and corresponding insulating layers of the same level from adjacent memory blocks.