A semiconductor memory device according to an embodiment includes: a stacked body in which a plurality of first conductive layers and a plurality of first insulating layers are alternately stacked one by one and includes a stepped portion in which, a first pillar disposed in the stepped portion, the first pillar extending in a stacking direction of the stacked body; and a second pillar extending in the stacking direction within the stacked body, the second pillar forming a memory cell at each intersection with at least a part of the plurality of first conductive layers. The first pillar has a semiconductor layer or a second conductive layer extending in the stacking direction and serving as a core material of the first pillar, and a second insulating layer covering a side wall of the semiconductor layer or the second conductive layer and serving as a liner layer of the first pillar.

A semiconductor memory device according to an embodiment includes: a stacked body in which a plurality of first conductive layers and a plurality of first insulating layers are alternately stacked one by one and includes a stepped portion in which, a first pillar disposed in the stepped portion, the first pillar extending in a stacking direction of the stacked body; and a second pillar extending in the stacking direction within the stacked body, the second pillar forming a memory cell at each intersection with at least a part of the plurality of first conductive layers. The first pillar has a semiconductor layer or a second conductive layer extending in the stacking direction and serving as a core material of the first pillar, and a second insulating layer covering a side wall of the semiconductor layer or the second conductive layer and serving as a liner layer of the first pillar.

A method includes forming a trench in a semiconductor layer of a device wafer and depositing a liner on the trench sidewalls. The liner is removed from the trench bottom, and the trench is deepened anisotropically to form an extension fully along the trench, or locally by applying a mask. The semiconductor material is removed outwardly from the extension by etching to create a cavity wider than the trench and below the liner. A space formed by the trench and cavity is filled with electrically conductive material to form a buried interconnect rail comprising a narrow portion in the trench and a wider portion in the cavity. The wider portion can be contacted by a TSV connection, enabling a contact area between the connection and buried rail. The etching forms a wider rail portion at a location remote from active devices formed on the front surface of the semiconductor layer.

A multi-stack semiconductor device includes: a lower-stack transistor structure including a lower active region and a lower gate structure, the lower active region including a lower channel structure, and the lower gate structure surrounding the lower channel structure; an upper-stack transistor structure vertically stacked above the lower-stack transistor structure, and including an upper active region and an upper gate structure, the upper active region including an upper channel structure, and the upper gate structure surrounding the upper channel structure; and at least one gate contact plug contacting a top surface of the lower gate structure, wherein the lower gate structure and the upper gate structure have a substantially same size in a plan view, and wherein the lower gate structure is not entirely overlapped by the upper gate structure in a vertical direction.

A multi-stack semiconductor device includes: a lower-stack transistor structure including a lower active region and a lower gate structure, the lower active region including a lower channel structure, and the lower gate structure surrounding the lower channel structure; an upper-stack transistor structure vertically stacked above the lower-stack transistor structure, and including an upper active region and an upper gate structure, the upper active region including an upper channel structure, and the upper gate structure surrounding the upper channel structure; and at least one gate contact plug contacting a top surface of the lower gate structure, wherein the lower gate structure and the upper gate structure have a substantially same size in a plan view, and wherein the lower gate structure is not entirely overlapped by the upper gate structure in a vertical direction.

Techniques are provided to form semiconductor devices having a multi-layer spacer structure. In an example, a semiconductor device includes a semiconductor region extending between a source region and a drain region, and a gate layer extending over the semiconductor region. A spacer structure made up of one or more dielectric layers is present along a sidewall of the gate structure and along a sidewall of the source region or the drain region. The spacer structure has three different portions: a first portion along the sidewall of the gate, a second portion along the sidewall of the source or drain region, and a third portion that connects between the first two portions. The third portion of the spacer structure has a multi-layer configuration while the first and second portions have a fewer number of material layers.

Semiconductor devices and methods of manufacturing the semiconductor devices are described herein. A method includes forming a first etch stop layer from a portion of a gate mask, the gate mask extending between spacers adjacent a gate electrode, the gate electrode overlying a semiconductor fin. The method further includes forming a second etch stop layer adjacent the first etch stop layer, forming an opening through the second etch stop layer, and exposing the first etch stop layer by performing a first etching process. The method further includes extending the opening through the first etch stop layer and exposing the gate electrode by performing a second etching process. Once the gate electrode has been exposed, the method further includes forming a gate contact in the opening.

Semiconductor devices and methods of manufacturing the semiconductor devices are described herein. A method includes forming a first etch stop layer from a portion of a gate mask, the gate mask extending between spacers adjacent a gate electrode, the gate electrode overlying a semiconductor fin. The method further includes forming a second etch stop layer adjacent the first etch stop layer, forming an opening through the second etch stop layer, and exposing the first etch stop layer by performing a first etching process. The method further includes extending the opening through the first etch stop layer and exposing the gate electrode by performing a second etching process. Once the gate electrode has been exposed, the method further includes forming a gate contact in the opening.

A semiconductor device including a substrate including a cell array region and a connection region, an electrode structure stacked on the substrate, each of the electrodes including a line portion on the cell array region and a pad portion on the connection region, Vertical patterns penetrating the electrode structure, a cell contact on the connection region and connected to the pad portion, an insulating pillar below the cell contact, with the pad portion interposed therebetween may be provided. The pad portion may include a first portion having a top surface higher than the line portion, and a second portion including a first protruding portion, the first protruding portion extending from the first portion toward the substrate and covering a top surface of the insulating pillar.

A semiconductor device including a substrate including a cell array region and a connection region, an electrode structure stacked on the substrate, each of the electrodes including a line portion on the cell array region and a pad portion on the connection region, Vertical patterns penetrating the electrode structure, a cell contact on the connection region and connected to the pad portion, an insulating pillar below the cell contact, with the pad portion interposed therebetween may be provided. The pad portion may include a first portion having a top surface higher than the line portion, and a second portion including a first protruding portion, the first protruding portion extending from the first portion toward the substrate and covering a top surface of the insulating pillar.