Modeling of Statistical Variation Effects on DRAM Sense Amplifier Offset Voltage

With the downscaling in device sizes, process-induced parameter variation has emerged as one of the most serious problems. In particular, the parameter fluctuation of the dynamic random access memory (DRAM) sense amplifiers causes an offset voltage, leading to sensing failure. Previous studies indic...

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Bibliographic Details
Main Authors: Kyung Min Koo, Woo Young Chung, Sang Yi Lee, Gyu Han Yoon, Woo Young Choi
Format: Article
Language:English
Published: MDPI AG 2021-09-01
Series:Micromachines
Subjects:
Online Access:https://www.mdpi.com/2072-666X/12/10/1145
Description
Summary:With the downscaling in device sizes, process-induced parameter variation has emerged as one of the most serious problems. In particular, the parameter fluctuation of the dynamic random access memory (DRAM) sense amplifiers causes an offset voltage, leading to sensing failure. Previous studies indicate that the threshold voltage mismatch between the paired transistors of a sense amplifier is the most critical factor. In this study, virtual wafers were generated, including statistical V<sub>T</sub> variation. Then, we numerically investigate the prediction accuracy and reliability of the offset voltage of DRAM wafers using test point measurement for the first time. We expect that this study will be helpful in strengthening the in-line controllability of wafers to secure the DRAM sensing margin.
ISSN:2072-666X