Embodiments of 3D memory devices and methods for forming the same are disclosed. In an example, a 3D memory device includes a substrate, a peripheral circuit on the substrate, a memory stack including interleaved conductive layers and dielectric layers above the peripheral circuit, a P-type doped semiconductor layer above the memory stack, a plurality of channel structures each extending vertically through the memory stack into the P-type doped semiconductor layer, and a source contact above the memory stack and in contact with the P-type doped semiconductor layer. An upper end of each of the plurality of channel structures is flush with or below a top surface of the P-type doped semiconductor layer.

Provided is a memory device including a first gate, a second gate and an inter-gate dielectric layer. The first gate is buried in a substrate. The second gate includes metal and is disposed on the substrate. The inter-gate dielectric layer is disposed between the first and second gates. The inter-gate dielectric layer comprises a high-k layer having a dielectric constant of greater than about 10.

A three-dimensional semiconductor memory device including a first peripheral circuit including different decoder circuits, a first memory on the first peripheral circuit, the first memory including a first stack structure having first electrode layers stacked on one another and first inter-electrode dielectric layers therebetween, a first planarized dielectric layer covering an end of the first stack structure, and a through via that penetrates the end of the first stack structure, the through via electrically connected to one of the decoder circuits, and a second memory on the first memory and including a second stack structure having second electrode layers stacked on one another and second inter-electrode dielectric layers therebetween, a second planarized dielectric layer covering an end of the second stack structure, and a cell contact plug electrically connecting one of the second electrode layers to the through via.

A three-dimensional semiconductor memory device including a first peripheral circuit including different decoder circuits, a first memory on the first peripheral circuit, the first memory including a first stack structure having first electrode layers stacked on one another and first inter-electrode dielectric layers therebetween, a first planarized dielectric layer covering an end of the first stack structure, and a through via that penetrates the end of the first stack structure, the through via electrically connected to one of the decoder circuits, and a second memory on the first memory and including a second stack structure having second electrode layers stacked on one another and second inter-electrode dielectric layers therebetween, a second planarized dielectric layer covering an end of the second stack structure, and a cell contact plug electrically connecting one of the second electrode layers to the through via.

A method for forming a memory device includes providing an initial semiconductor structure, including a base substrate; a first sacrificial layer formed on the base substrate; a stack structure, disposed on the first sacrificial layer; a plurality of channels, formed through the stack structure and the first sacrificial layer; and a gate-line trench, formed through the stack structure and exposing the first sacrificial layer. The method also includes forming at least one protective layer on the sidewalls of the gate-line trench; removing the first sacrificial layer to expose a portion of each of the plurality of channels and the surfaces of the base substrate, using the at least one protective layer as an etch mask; and forming an epitaxial layer on the exposed surfaces of the base substrate and the plurality of channels.

A semiconductor device including a substrate that includes a cell array region and a peripheral circuit region; a cell transistor on the cell array region of the substrate; a peripheral transistor on the peripheral circuit region of the substrate; a first interconnection layer connected to the cell transistor; a second interconnection layer connected to the peripheral transistor; an interlayer dielectric layer covering the first interconnection layer; and a blocking layer spaced apart from the first interconnection layer, the blocking layer covering a top surface and a sidewall of the second interconnection layer.

A semiconductor device including a substrate that includes a cell array region and a peripheral circuit region; a cell transistor on the cell array region of the substrate; a peripheral transistor on the peripheral circuit region of the substrate; a first interconnection layer connected to the cell transistor; a second interconnection layer connected to the peripheral transistor; an interlayer dielectric layer covering the first interconnection layer; and a blocking layer spaced apart from the first interconnection layer, the blocking layer covering a top surface and a sidewall of the second interconnection layer.

A 3D semiconductor memory device includes a substrate, a stack structure comprising interlayer dielectric layers and gate electrodes alternately and repeatedly stacked on the substrate, vertical channel structures penetrating the stack structure, a separation structure spaced apart from the vertical channel structures and filling a trench crossing the stack structure, the separation structure comprising a spacer covering an inner sidewall of the trench, and a first conductive contact filling an inner space of the trench surrounded by the spacer, an insulating layer covering the substrate and the stack structure, contact plugs penetrating the insulating layer so as to be connected to the gate electrodes of the stack structure, and a second conductive contact spaced apart from the stack structure and penetrating the insulating layer so as to be connected to a peripheral circuit transistor. A bottom surface of the first conductive contact is at a level lower than a bottom surface of the spacer.

A three-dimensional memory device includes an electrode structure including a plurality of interlayer dielectric layers and a plurality of electrode layers which are alternately stacked on a first substrate, each of the plurality of electrode layers having a pad part which does not overlap with another electrode layer positioned on the electrode layer; a pass transistor positioned below the first substrate; and a first contact passing through the electrode structure from the pad part of one of the plurality of electrode layers, and coupling the pad part and the pass transistor.

A three-dimensional memory device can include at least one alternating stack of insulating layers and electrically conductive layers located over a semiconductor material layer, memory stack structures vertically extending through the at least one alternating stack, and a vertical stack of dielectric plates interlaced with laterally extending portions of the insulating layers of the at least one alternating stack. A conductive via structure can vertically extend through each dielectric plate and the insulating layers, and can contact an underlying metal interconnect structure. Additionally or alternatively, support pillar structures can vertically extend through the vertical stack of dielectric plates and into an opening through the semiconductor material layer, and can contact lower-level dielectric material layers embedding the underlying metal interconnect structure to enhance structural support to the three-dimensional memory device during manufacture.