Go, D.; Yoon, G.; Park, J.; Kim, D.; Kim, J.; Kim, J.; Lee, J.-S. Effect of Noncircular Channel on Distribution of Threshold Voltage in 3D NAND Flash Memory. Micromachines2023, 14, 2007.
Go, D.; Yoon, G.; Park, J.; Kim, D.; Kim, J.; Kim, J.; Lee, J.-S. Effect of Noncircular Channel on Distribution of Threshold Voltage in 3D NAND Flash Memory. Micromachines 2023, 14, 2007.
Go, D.; Yoon, G.; Park, J.; Kim, D.; Kim, J.; Kim, J.; Lee, J.-S. Effect of Noncircular Channel on Distribution of Threshold Voltage in 3D NAND Flash Memory. Micromachines2023, 14, 2007.
Go, D.; Yoon, G.; Park, J.; Kim, D.; Kim, J.; Kim, J.; Lee, J.-S. Effect of Noncircular Channel on Distribution of Threshold Voltage in 3D NAND Flash Memory. Micromachines 2023, 14, 2007.
Abstract
Variations in threshold voltage (VTH) and charge distributions in noncircular cells of three-dimensional (3D) NAND flash memory are investigated. The electric field difference in the circular and spike regions causes nonuniform trapped electron density in the charge trap layer (CTL) and influences the VTH variation. Such less-trapped electron (LT) regions in CTL between the circular and spike regions exhibit a lower electric field during the program, resulting in a higher current flow through that region. For the two-spike cells, the charge distribution and VTH variation are analyzed at different heights (HSpike) and angles between spikes. These irregular cells decrease VTH as the HSpike increases.
Keywords
3D NAND flash memory; noncircular cell; spike; TCAD simulation; threshold voltage variation; trapped charge
Subject
Engineering, Electrical and Electronic Engineering
Copyright:
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