标题：Retention Correlated Read Disturb Errors in 3D Charge Trap NAND Flash Memory: Observations, Analysis, and Solutions
作者：Kong Y.; Zhang M.; Zhan X.; Cao R.; Chen J.
作者机构：[Kong, Y] School of Information Science and Engineering (ISE), Shandong University, Qingdao, China. 266237. (e-mail: email@example.com);[ Zhang, M] W 更多
来源：IEEE Transactions on Computer-Aided Design of Integrated Circuits and Systems
关键词：3D NAND Flash Memory; Data Retention; Flash memories; PCSL; Read Disturb; Thermal stability; Three-dimensional displays; TSSL.; Tunneling; Two dimensional displays
摘要：3D NAND flash memory has been attracting much attention owing to its ultra-high storage density and low bit cost, and it has been widely applied in data centers and mobiles. 3D triple-level-cell (TLC) NAND flash memory can achieve much larger storage capacity by storing 3 bits in each cell. However, the data reliability issues induced by data retention (DR) and read disturb (RD) greatly limit 3D TLC NAND applications in hot data storage where the stored data are frequently accessed and RD is more serious. In this paper, we first systematically study the retention correlated read disturb errors (RCRD) in 3D charge trap (CT) TLC NAND flash memory under various conditions. Error characteristics and underlying mechanisms much different from 2D NAND flash memory are observed: 1) for RCRD with short retention-after data program, error bits increase due to the negative-shift of program states; 2) for RCRD with long retention-after retention 12 hours, error bits can be partially recovered on the contrary due to the charge compensation. We propose schemes of pre-charge the storage layer (PCSL) and thermally stabilize storage layer (TSSL) to improve the reliability of 3D NAND flash memory. By using these two methods, experimental results show that raw bit error rates (RBER) can be significantly reduced by 30% and 20%, respectively. IEEE