Patent ID: 11895838
Assignee: SAMSUNG ELECTRONICS CO., LTD.
Field: Semiconductors (Electrical engineering)
Classification: CPC H | IPC H

Claim 18:
19. A vertical memory device comprising:
a first gate electrode structure on a substrate, the first gate electrode structure including first gate electrodes spaced apart from each other in a first direction substantially perpendicular to an upper surface of the substrate and sequentially stacked in a staircase shape, and each of the first gate electrodes extending in a second direction substantially parallel to the upper surface of the substrate;
a second gate electrode structure on the first gate electrode structure, the second gate electrode structure including second gate electrodes spaced apart from each other in the first direction and sequentially stacked in the staircase shape, and each of the second gate electrodes extending in the second direction;
a channel extending on the substrate in the first direction through the first and second gate electrode structures;
first contact plugs, each extending in the first direction through the first and second gate electrode structures; and
second contact plugs, each extending in the first direction through the first and second gate electrode structures,
wherein second steps at end portions in the second direction of the second gate electrodes, respectively, overlap in the first direction and are aligned in the first direction with first steps at end portions in the second direction of the first gate electrodes, respectively, the first and second steps that are aligned with each other in the first direction extending to a same length in the second direction,
wherein each of the first contact plugs includes:
a first vertical portion extending in the first direction through the first and second gate electrode structures, and
a first protrusion portion protruding from the first vertical portion in a horizontal direction substantially parallel to the upper surface of the substrate,

wherein the first protrusion portion of each of the first contact plugs contacts an upper surface of a corresponding one of the first gate electrodes to be electrically connected thereto,
wherein each of the second contact plugs includes:
a second vertical portion extending in the first direction through the first and second gate electrode structures, and
a second protrusion portion protruding from the second vertical portion in the horizontal direction,

wherein the second protrusion portion of each of the second contact plugs contacts an upper surface of a corresponding one of the second gate electrodes to be electrically connected thereto, and
wherein a first length in the second direction of an uppermost one of the first electrodes is shorter than a second length in the second direction of a lowermost one of the second electrodes, and a third length in the second direction of a lowermost one of the first electrodes equals the second length in the second direction of the lowermost one of the second electrodes.