Stepped Memory Structure Barrier Layer Prevents Cell Bridging
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In 3D nonvolatile memory devices with vertically stacked memory cells, the protrusions between memory cells can lead to a bridge formation, compromising the memory cell characteristics and operation due to insufficient distance between cells.
Innovation Solution
A semiconductor device with a stepped structure featuring alternately stacked interlayer dielectric and conductive layers, where a barrier layer with insulating material is formed on the sidewalls of the conductive layers, preventing bridges by maintaining a secure distance between memory cells, and a method involving radical oxidation and wet etching processes to fabricate this structure.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Quantity of substance
If memory cells are vertically stacked to increase integration density, then the integration density is improved, but the distance between memory cells becomes insufficient leading to bridge formation
Solution Approach 1:
A barrier layer is introduced as an intermediary structure between adjacent conductive layers in the vertically stacked memory cells. This barrier layer, formed on the sidewalls of the conductive layers, acts as a physical mediator that prevents direct contact and bridge formation between neighboring memory cells, thereby maintaining reliable cell operation while enabling high integration density through vertical stacking.
2Reliability
If protrusions are formed on conductive layers to enhance memory cell characteristics, then the memory cell characteristic is improved, but the distance between adjacent cells is reduced causing bridge formation
Solution Approach 1:
The barrier layer serves as a protective intermediary that compensates for the space occupied by protrusions on conductive layers. By forming this insulating barrier on the sidewalls, the design allows protrusions to be present for enhanced memory characteristics while the barrier layer ensures that the protrusions of adjacent cells do not contact, preventing bridge formation.
3Reliability
If a barrier layer is formed on sidewalls of conductive layers to prevent bridges, then the reliability is improved, but the device structure becomes more complex
Solution Approach 1:
The barrier layer is formed preliminarily on the sidewalls of the conductive layers during the fabrication process, before final assembly and operation. This preliminary formation of the protective barrier structure ensures that subsequent processing steps and the final device operation can proceed without bridge formation issues, even though the overall device structure becomes more complex.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The solution effectively prevents bridges between memory cells, ensuring secure memory cell characteristics and operation by maintaining a larger distance between conductive layers, thereby enhancing the performance and reliability of the semiconductor device.
Implementation Method 1
a barrier layer formed on a sidewall of each of the conductive layers over each of the first interlayer dielectric layers
Implementation Method 2
The barrier layers may be formed through an oxidation process. The barrier layers may be formed through a radical oxidation process.
Data Source
AI summary
Provided is an electronic device including a semiconductor memory. The semiconductor memory may include: a substrate; and a stepped structure including first interlayer dielectric layers and conductive layers which are alternately stacked over the substrate, wherein ends of the conductive layers are exposed along the profile of the stepped structure, and the stepped structure further includes a barrier layer formed on a sidewall of the conductive layer.