Random Telegraph Noise-Induced Sensitivity of Data Retention to Cell Position in the Programmed Distribution of NAND Flash Memory Arrays

This letter highlights a random telegraph noise-induced sensitivity of the data retention threshold-voltage transient of nand Flash memory cells to their position in the programmed array distribution. This sensitivity appears with a reduction of the threshold-voltage loss of the cells in the lower part of the programmed distribution of the memory array and an increase of that of the cells in the upper part of the distribution. The experimental evidence is explained considering the impact of random telegraph noise on the programmed array distribution in the stretch of time in-between the program-and-verify operation and the first read operation used as reference for data retention assessment.