3D Memory Word-Line Stack with Stepped Support Structure

Solution Overview

Problem

The stability of manufacturing processes and structural stability is compromised as the number of stacked word lines increases in three-dimensional semiconductor memory devices, affecting the integration and performance of the devices.

Innovation Solution

A semiconductor memory device is designed with a first stack and a second stack of conductive patterns separated by insulating layers, featuring a stepped structure and support pillars to enhance structural stability, along with a channel structure and memory layer to improve manufacturing process stability.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Quantity of substance

If the number of stacked word lines is increased to increase the degree of integration, then the integration density is improved, but the manufacturing process stability and structural stability are deteriorated

Engineering Contradiction:

Improvenumber of stacked word linesVSAvoidmanufacturing process stability

Core Design Contradiction:

Quantity of substanceVSReliability

Solution Approach 1:

The gate electrode stack is divided into multiple segments with different widths at different heights, forming a stepped structure. This segmentation reduces the overall width of the gate electrode stack while maintaining the number of stacked word lines, thereby improving manufacturing process stability and structural integrity without sacrificing integration density.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The patent transitions from a two-dimensional planar arrangement to a three-dimensional stepped structure by varying the width of gate electrode segments at different heights. This dimensional change allows for increased integration density through vertical stacking while controlling the horizontal footprint to maintain manufacturing stability.

Inventive Principle:

Principle #17Another dimension (Dimensionality change)

2Quantity of substance

If the number of stacked word lines is increased to increase the degree of integration, then the integration density is improved, but the structural stability is deteriorated

Engineering Contradiction:

Improvenumber of stacked word linesVSAvoidstructural stability

Core Design Contradiction:

Quantity of substanceVSStability of the object's composition

Solution Approach 1:

The gate electrode stack is divided into multiple segments with different widths at different heights, forming a stepped structure. This segmentation reduces the overall width of the gate electrode stack while maintaining the number of stacked word lines, thereby improving manufacturing process stability and structural integrity without sacrificing integration density.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The patent employs asymmetric gate electrode segments where each segment has a different width, creating a stepped profile. This asymmetric design optimizes the structural distribution of stress and enhances structural stability while maintaining high integration density through efficient space utilization.

Inventive Principle:

Principle #4Asymmetry

3Manufacturing precision

If the gate electrode stack width is reduced to improve manufacturing stability, then the manufacturing precision is improved, but the integration density is reduced

Engineering Contradiction:

Improvemanufacturing stabilityVSAvoidintegration density

Core Design Contradiction:

Manufacturing precisionVSQuantity of substance

Solution Approach 1:

The patent transitions from a two-dimensional planar arrangement to a three-dimensional stepped structure by varying the width of gate electrode segments at different heights. This dimensional change allows for increased integration density through vertical stacking while controlling the horizontal footprint to maintain manufacturing stability.

Inventive Principle:

Principle #17Another dimension (Dimensionality change)

Solution Approach 2:

The gate electrode stack is divided into multiple segments with different widths at different heights, forming a stepped structure. This segmentation reduces the overall width of the gate electrode stack while maintaining the number of stacked word lines, thereby improving manufacturing process stability and structural integrity without sacrificing integration density.

Inventive Principle:

Principle #1Segmentation

Data Source

PatentUS12382631B2Semiconductor memory device and manufacturing method of the semiconductor memory device

Publication Date: 2025.08.05 SK HYNIX INC

AI summary

A semiconductor memory device includes a first stack including lower conductive patterns separated from each other and stacked on a substrate to form a lower stepped structure, a support pillar passing through the first stack and including an insulating layer, a second stack including upper conductive patterns separated from each other and stacked on the first stack, the upper conductive patterns including an upper stepped structure that does not overlap with the lower stepped structure and the support pillar, a channel structure passing through the second stack and the first stack, and a memory layer surrounding a sidewall of the channel structure.