Method for compacting the erased threshold voltage distribution of flash memory devices during writing operations

摘要

A method for operating a flash memory device. The memory device includes a matrix of memory cells each one having a programmable threshold voltage defining a value stored in the memory cell. The method includes the steps of erasing a block of memory cells, and compacting the threshold voltages of the memory cells of the block within a predefined compacting range, wherein the step of compacting includes: selecting at least one first memory cell of the block for writing a target value; restoring the threshold voltage of a subset of the memory cells of the block to the compacting range, the subset including the at least one first memory cell and/or at least one second memory cell of the block being adjacent to the at least one first memory cell; and at least partially writing the target value into the at least one first memory cell.