一种用于NAND闪存的奇偶位线块编程补偿算法

An Even-Odd BL Chucks Programming Compensation Algorithm Applied in NAND Flash

为改善数据保持干扰和编程干扰对NAND闪存可靠性的影响,提出了一种新的奇偶位线块编程补偿算法。该算法利用编程干扰效应来补偿由数据保持引起的阈值漂移,修复NAND闪存因数据保持产生的误码,提高了NAND闪存的可靠性。将该算法应用于编程擦除次数为3k次的1x-nm MLC NAND闪存。实验结果表明,在数据保持时间为1年的条件下,与传统奇偶交叉编程算法相比,采用该补偿算法的NAND闪存的误码降低了93%;与读串扰恢复算法相比,采用该补偿算法的NAND闪存的误码下降了38%。

A novel programming compensation algorithm based on even-odd BL chunks was proposed according to the failure mechanism of data retention and program disturbance.The proposed algorithm used program disturbance to compensate the threshold shift caused by data retention.As a result,the error bits induced by data retention could be corrected and the reliability of NAND flash memories could be improved.The algorithm was applied in 1 x-nm MLC NAND flash memories with 3 kprogram-erase（PE）cycling.The experimental results showed that this compensation algorithm could reduce 93% of the bit errors in NAND flash memory when the data retention time was one year.Compared with the algorithm that used the read crosstalk,the proposed programming compensation algorithm could reduce 38% of error bits.