Semiconductor device and electronic system including the same

A semiconductor device comprising:

• a first substrate structure including a substrate, circuit elements on the substrate, and first bonding layers on the circuit elements;
• and
• a second substrate structure on the first substrate structure,
• wherein the second substrate structure includes
• a plate layer,
• an intermediate insulating layer below the plate layer and including silicon nitride,
• gate electrodes below the intermediate insulating layer and stacked to be spaced apart from each other in a first direction, the first direction being perpendicular to a lower surface of the intermediate insulating layer,
• a channel structure in a channel hole passing through the intermediate insulating layer and the gate electrodes and extending in the first direction, the channel structure including a semiconductor layer, and
• second bonding layers below the gate electrodes and connected to the first bonding layers,
• wherein the channel hole has a first width in a first portion passing through the gate electrodes and a second width in a second portion passing through the intermediate insulating layer, the second width being wider than the first width, and
• the plate layer includes a protrusion in contact with the semiconductor layer in the second portion.

An electronic system comprising:

• a semiconductor storage device including a first substrate structure including circuit elements and first bonding layers, a second substrate structure including second bonding layers connected to the first bonding layers, and an input/output pad electrically connected to the circuit elements;
• and
• a controller electrically connected to the semiconductor storage device through the input/output pad and configured to control the semiconductor storage device,
• wherein the second substrate structure include
• a plate layer,
• an intermediate insulating layer below the plate layer and including silicon nitride,
• gate electrodes below the intermediate insulating layer and stacked to be spaced apart from each other in a first direction, the first direction being perpendicular to a lower surface of the intermediate insulating layer, and
• a channel structure in a channel hole passing through the intermediate insulating layer and the gate electrodes, and extending in the first direction, the channel structure including a semiconductor layer,
• wherein the channel hole has a first width in a first portion passing through the gate electrodes and a second width in a second portion passing through the intermediate insulating layer, the second width being wider than the first width, and
• the plate layer includes a protrusion in contact with the semiconductor layer in the second portion.