Three-dimensional memory device and manufacturing method thereof
AssigneeSK hynix Inc.
InventorsSung Lae OH, Jin Ho KIM, Sang Woo PARK, Sang Hyun SUNG
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Abstract
A three-dimensional memory device includes an electrode structure including a plurality of electrode layers and a plurality of interlayer dielectric layers which are alternately stacked on a substrate; a first stairway structure and a second stairway structure defined in the electrode structure, and positioned at different heights from each other; a sidewall of the electrode structure formed due to a difference in height between the first stairway structure and the second stairway structure; and a dielectric support passing through the electrode structure, and isolating a corner portion of the sidewall from the plurality of electrode layers.
Claims20
A three-dimensional memory device comprising:
- an electrode structure including a plurality of electrode layers and a plurality of interlayer dielectric layers, which are alternately stacked on a substrate;
- a first stairway structure and a second stairway structure, defined in the electrode structure, and positioned at different heights from each other;
- a sidewall of the electrode structure between the first stairway structure and the second stairway structure;
- and
- a dielectric support passing through the electrode structure and isolating a corner portion of the sidewall from the plurality of electrode layers.
A method for manufacturing a three-dimensional memory device, comprising:
- forming a pre-stack by alternately stacking a plurality of interlayer dielectric layers and a plurality of sacrificial layers on a substrate;
- forming a dielectric support, which passes through the pre-stack;
- forming a first stairway structure on a top of the pre-stack in a slimming region;
- forming a second stairway structure by transferring a part of the first stairway structure downward by etching the pre-stack;
- and
- substituting the sacrificial layers with electrode layers,
- wherein, in the forming of the second stairway structure, a corner portion of a sidewall that is formed in the pre-stack by the etching is isolated from the plurality of sacrificial layers by the dielectric support.
A method for manufacturing a three-dimensional memory device, comprising:
- forming a pre-stack by alternately stacking a plurality of interlayer dielectric layers and a plurality of sacrificial layers on a substrate;
- forming a first stairway structure on a top of the pre-stack;
- forming a second stairway structure by transferring a part of the first stairway structure downward by etching the pre-stack;
- forming a vertical hole which passes through the pre-stack, in the vicinity of a corner portion of a sidewall, which is formed in the pre-stack in the forming of the second stairway structure;
- forming a plurality of horizontal grooves by removing the plurality of sacrificial layers, formed at the corner portion, through the vertical hole;
- forming a dielectric support in the vertical hole and the plurality of horizontal grooves;
- and
- substituting the sacrificial layers with electrode layers.
Dependencies are inferred from the claim text.