3D Semiconductor Memory Stack Layout for Uniform Pitch Reliability
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Two-dimensional semiconductor devices face limitations in integration due to the need for expensive process equipment to increase pattern fineness, which hinders the development of high-density memory devices.
Innovation Solution
A three-dimensional semiconductor memory device with a stack structure comprising first and second blocks, separation structures, vertical channel structures, and through-via structures, where the width of the first blocks equals the width of the second blocks, facilitating uniform pitch and improved electrical characteristics.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If two-dimensional or planar semiconductor devices are used, then manufacturing process is simpler, but integration is greatly influenced by pattern fineness and requires expensive process equipment
Solution Approach 1:
The patent transitions from two-dimensional planar semiconductor devices to three-dimensional vertically stacked memory structures. Multiple memory layers are stacked in the vertical direction, allowing high integration density without requiring finer lateral patterning. This dimensional change enables increased capacity while avoiding the need for expensive fine-patterning equipment.
2Productivity
If pattern fineness is increased to improve integration, then data storage capacity increases, but expensive process equipment is needed
Solution Approach 1:
Instead of increasing lateral pattern fineness, the patent stacks multiple memory layers vertically. This approach achieves high integration density by utilizing the vertical dimension, thereby avoiding the need for expensive fine-patterning equipment while maintaining manufacturability.
Solution Approach 2:
The memory device is divided into multiple discrete layers stacked vertically, with each layer containing memory cells. This segmentation allows each layer to be formed using standard patterning processes, avoiding the need for single-step fine-patterning across the entire device area.
3Adaptability or versatility
If block widths are non-uniform in the stack structure, then design flexibility increases, but pitch uniformity and electrical characteristics deteriorate
Solution Approach 1:
The patent applies different characteristics to different regions: the block structures have uniform widths to ensure pitch uniformity and reliable electrical characteristics, while the overall stack structure provides design flexibility through variable numbers of layers and configurable interconnect arrangements. This local uniformity in critical dimensions maintains electrical performance.
Solution Approach 2:
The patent maintains uniform block widths as a fixed parameter to ensure pitch uniformity across the device. This parameter control ensures consistent electrical characteristics while other parameters such as the number of stacked layers and interconnect configurations can be varied to achieve design flexibility.
Data Source
AI summary
A three-dimensional semiconductor memory device includes a substrate, and a stack structure on the substrate. The stack structure includes first blocks that extend in a first direction and are arranged in a second direction intersecting the first direction, and a second block that is between the first blocks; separation structures that extend in the first direction and are arranged in the second direction between the first blocks and between the first and second blocks; vertical channel structures that penetrate the first blocks and contact the substrate; and through-via structures that penetrate the second block and the substrate. A width of each of the first blocks in the second direction is equal to a width of the second block in the second direction.