METHOD FOR READING A RESISTIVE MEMORY CELL, AND A MEMORY CELL FOR IMPLEMENTATION

摘要

The invention has involved the development of a method for reading a resistive memory cell that has two electrodes spaced apart from one another by an ion-conductive resistive material and that can be transferred from a stable state having a relatively high resistance value (high resistive state, HRS) to a stable state having a relatively low resistance value (low resistance state, LRS) by applying a write voltage. According to the invention, reading involves a read voltage being applied as a read pulse, wherein the number of ions driven through the ion-conductive resistive material during the pulse is set by means of the level and duration of the pulse such that, on the basis of the state for forming an electrically conductive path through the ion-conductive resistive material, they suffice at least until the onset of a flow of current through this path and hence for the transition to a metastable state VRS (volatile resistance state) with a reduced resistance value and a prescribed relaxation time for the return to the HRS state, but not for the transition to the LRS state. This ensures that the memory cell is always back in the same state after reading as before reading. This renders particularly memory elements that consist of two memory cells in reverse-connected series being nondestructively readable without this diminishing the possibility of producing large arrays from these memory elements.