Semiconductor devices

A semiconductor device comprising:

• a gate electrode structure including gate electrodes spaced apart from each other in a first direction perpendicular to an upper surface of a substrate;
• a blocking pattern covering upper surfaces, lower surfaces, and sidewalls of the gate electrodes, wherein the blocking pattern comprises a metal oxide;
• insulation patterns disposed between the gate electrodes;
• a first capacitor electrode extending through the gate electrode structure and the insulation patterns in the first direction;
• a dielectric pattern on a sidewall of the first capacitor electrode;
• and
• second capacitor electrodes having portions of the gate electrodes adjacent to the first capacitor electrode,
• wherein an outer radius from a central axis of the first capacitor electrode to an outer sidewall of the first capacitor electrode periodically increases and decreases along the first direction, and
• wherein the outer radius increases at heights corresponding to the insulation patterns.

A semiconductor device comprising:

• a gate electrode structure including gate electrodes spaced apart from each other in a first direction substantially perpendicular to an upper surface of a substrate;
• a memory channel structure including:
• a channel extending through the gate electrode structure in the first direction;
• and
• a charge storage structure on an outer sidewall of the channel;
• a capacitor structure extending through the gate electrode structure and spaced apart from the memory channel structure in a horizontal direction parallel to the upper surface of the substrate,
• wherein the capacitor structure includes:
• a first capacitor electrode extending in the first direction;
• a dielectric pattern on a sidewall of the first capacitor electrode;
• and
• second capacitor electrodes having portions of the gate electrodes adjacent to the first capacitor electrode, and
• wherein the first capacitor electrode includes protrusion portions that protrude in the horizontal direction between adjacent ones of the gate electrodes in the first direction.