| abstract |
Embodiments of 3D memory devices and methods for forming the same are disclosed. In an example, a method for forming a 3D memory device is disclosed. A sacrificial layer on the substrate, an N-type doped semiconductor layer on the sacrificial layer, and a dielectric stack on the N-type doped semiconductor layer are sequentially formed. A channel structure is formed extending vertically through the dielectric stack and the N-type doped semiconductor layer. The dielectric stack is replaced with a memory stack such that the channel structure extends vertically through the memory stack and the N-type doped semiconductor layer. The substrate and sacrificial layer are removed to expose the ends of the channel structures. The portion of the channel structure adjoining the N-type doped semiconductor layer is replaced with a semiconductor plug. |