Segmented Word Line Layout for High-Capacity Memory Arrays
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
As memory devices increase in integration and storage capacity, the size of memory blocks increases, leading to longer wirings and deteriorated operation characteristics due to increased resistance in word lines.
Innovation Solution
The memory device is divided into two cell array regions separated by a separation region, with the word lines in each region connected through shorter connection lines and, in some cases, an upper metal line, reducing resistance and improving operation efficiency.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Quantity of substance
If the number of channel structures is increased to improve integration and storage capacity, then the storage capacity and integration level are improved, but the size of memory blocks increases and word line resistance increases causing operation characteristics to deteriorate
Solution Approach 1:
The memory block is divided into two separate cell array regions (first cell array region and second cell array region) with each region having its own set of word lines. This segmentation allows independent optimization of each region's word line connections, reducing the overall resistance impact on operation characteristics while maintaining high storage capacity through increased channel structures.
2Quantity of substance
If the size of memory blocks is increased to accommodate more channel structures, then the storage capacity is improved, but the wiring length increases and operation characteristics deteriorate
Solution Approach 1:
By segmenting the memory block into two cell array regions, each region can have shorter local word line connections. The first word lines connect within the first cell array region and the second word lines connect within the second cell array region, reducing the overall wiring length compared to a single large memory block while maintaining high storage capacity.
3Quantity of substance
If the word line length is increased to connect memory cells across larger memory blocks, then the storage capacity is improved, but the resistance increases and operation characteristics deteriorate
Solution Approach 1:
The word lines are segmented into first word lines for the first cell array region and second word lines for the second cell array region. This segmentation ensures that each word line connects only to memory cells within its respective region, reducing word line length and resistance while maintaining high storage capacity through the combined capacity of both regions.
Solution Approach 2:
The separation region acts as an intermediary structure between the first and second cell array regions. It provides a boundary that allows independent word line connections in each region while maintaining overall memory block functionality, effectively reducing word line resistance without compromising storage capacity.
4Quantity of substance
If the number of wirings is increased to connect more memory cells, then the storage capacity is improved, but the device complexity increases and operation characteristics deteriorate
Solution Approach 1:
By segmenting the memory block into two cell array regions with separate word line connections, the complexity of wiring is reduced. Each region has its own simplified wiring structure, avoiding the need for complex long-distance connections across a single large memory block, while maintaining high storage capacity through the combined capacity of both regions.
Data Source
AI summary
A memory device includes a first cell array region and a second cell array region separated by a separation region, each including at least one memory block having a plurality of gate electrode layers stacked in a first direction. The gate electrode layers include an upper select electrode layer including a plurality of string select lines, and a first electrode layer including a plurality of first word lines arranged below the string select lines. The first word lines include a first connection line to connect first end portions of the first word lines positioned on the opposite side of the separation region to each other and a plurality of second connection lines to connect some of second end portions of the plurality of first word lines adjacent to the separation region to each other, wherein each of the second connection lines is shorter than the first connection line.