R&D: Characterization Summary of Performance, Reliability, and Threshold Voltage Distribution of 3D Charge-Trap NAND Flash

ACM Transactions on Storage has published an article written by Weihua Liu, Fei Wu, Xiang Chen, Meng Zhang, Yu Wang, Huazhong University of Science and Technology, Wuhan, Hubei, China, Xiangfeng Lu, Beijing Memblaze Technology Co., Ltd., Beijing, China, and , Changsheng Xie, Huazhong University of Science and Technology, Wuhan, Hubei, China.

Abstract: “Solid-state drive (SSD) gradually dominates in the high-performance storage scenarios. Three-dimension (3D) NAND flash memory owning high-storage capacity is becoming a mainstream storage component of SSD. However, the interferences of the new 3D charge-trap (CT) NAND flash are getting unprecedentedly complicated, yielding to many problems regarding reliability and performance. Alleviating these problems needs to understand the characteristics of 3D CT NAND flash memory deeply. To facilitate such understanding, in this article, we delve into characterizing the performance, reliability, and threshold voltage (V_th) distribution of 3D CT NAND flash memory. We make a summary of these characteristics with multiple interferences and variations and give several new insights and a characterization methodology. Especially, we characterize the skewed (V_th) distribution, (V_th) shift laws, and the exclusive layer variation in 3D NAND flash memory. The characterization is the backbone of designing more reliable and efficient flash-based storage solutions.“