Patent ID: 9472271
Filing Date: 2016-10-18
CPC Classification: G11C

Claim Text:
1. A method for pre-programming a matrix of phase-change memory cells, including a phase-change material positioned between two conducting electrodes, said phase-change material being able to be reversely electrically modified so as to vary the resistivity of the memory cell, wherein at least a dielectric layer is provided, which is positioned between the two conducting electrodes, with the memory cell having an original resistive state (original HRS) at the end of the memory cell production process, the method comprising: executing a step of pre-programming the matrix is executed prior to a step of mounting a component containing said matrix onto a support, with the step of pre-programming including applying a breakdown voltage to a selected portion of all the memory cells based on coded data to be stored in the matrix so that, for each one of the selected cells, the layer of the dielectric material breaks down to bring the cell from the original resistive state (original HRS) to a second resistive state (breakdown LRS), so that the cells which were, prior to mounting, in said original resistive state (original HRS) and in said second resistive state (breakdown LRS) are, after the step of mounting, in a third resistive state (mounting HRS) and in a fourth resistive state (mounting LRS), respectively, and in that the resistance of the cells in said third resistive state (mounting HRS) is at least twice higher than the resistance of the cells in said fourth resistive state (mounting LRS); and after mounting, reading the resistive state of all the cells in the matrix so as to identify the cells which are, after mounting, in said third resistive state (mounting HRS) and those which are in said fourth resistive state (mounting LRS).