Real usage-based precise reliability test by extracting read/write/retention-mixed real-life access of NAND flash memory from system-level SSD emulator

Real usage-based precise reliability test for NAND flash of SSDs and reliability boost guidelines are proposed. Conventional simple reliability tests of data-retention and read-disturb cannot reproduce the real-life Vth shift and memory cell errors. The proposed reliability test method precisely reproduces the real memory cell failures by emulating the complicated read, write, and data-retention with SSD emulator. Based on the proposed reliability test, the guidelines of the read reference voltage shift are proposed to achieve the highest memory cell reliability for two kinds of real workloads.