Retired Wordline Programming at Active Boundary Wordlines
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Programming retired wordlines in memory devices leads to negative pillar potential regions and charge loss migration, affecting active data wordlines, resulting in increased error rates and reduced performance due to the need for dummy data programming, which consumes time and system resources.
Innovation Solution
Program specific data patterns in selected retired wordlines adjacent to active data wordlines, using median and high threshold voltage levels to mitigate negative pillar potential and charge loss, reducing the number of programmed retired wordlines to improve performance.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If all retired wordlines are programmed with dummy data, then charge loss migration and negative pillar potential are mitigated, but programming time and system resources are consumed
Solution Approach 1:
Instead of uniformly programming all retired wordlines, the patent applies local quality by selectively programming only boundary retired wordlines (those adjacent to active data wordlines) while skipping inner retired wordlines. This localized approach mitigates charge loss migration and negative pillar potential effects at critical boundaries without the time cost of programming all retired wordlines throughout the memory array.
Solution Approach 2:
The patent extracts the harmful effect (charge loss migration and negative pillar potential) from the entire memory array by removing the unnecessary programming operation from non-boundary retired wordlines. Only the essential boundary wordlines are programmed, extracting the harmful effects from the bulk of the memory structure where they do not significantly impact active data wordlines.
2Reliability
If dummy data is programmed in all retired wordlines, then negative pillar potential regions are eliminated, but throughput is reduced
Solution Approach 1:
The patent applies local quality by programming only boundary retired wordlines adjacent to active data wordlines, while skipping inner retired wordlines. This selective approach eliminates negative pillar potential regions at critical boundaries where they would otherwise form and impact data reliability, without the throughput penalty of programming all retired wordlines throughout the memory array.
3Reliability
If all retired wordlines are programmed, then charge loss migration is prevented, but power consumption increases
Solution Approach 1:
The patent applies local quality by programming only boundary retired wordlines (those adjacent to active data wordlines) while skipping inner retired wordlines. This localized programming approach prevents charge loss migration at critical boundaries where it would otherwise occur, without the excessive power consumption of programming all retired wordlines throughout the entire memory array.
Data Source
AI summary
A memory device comprises an array of memory cells organized into a plurality of wordlines, and a processing device to perform processing operations that receive a program command specifying a memory unit and data comprising first received data, where the plurality of wordlines includes one or more first active data wordlines and a group of consecutive retired wordlines. The processing operations also program the specified data to the memory unit by programming the first received data to the one or more first active data wordlines, identifying a first retired boundary wordline that is in the group of consecutive retired wordlines and is adjacent to one of the first active data wordlines, generating a first data pattern comprising a first plurality of threshold voltage levels, and programming the first data pattern to the first retired boundary wordline.