Patent ID: 8681531
Filing Date: 2014-03-25
Classification: G11C,H01L

Abstract:
1. A method of forming a memory cell, comprising: forming a first region of a programmable material over a first access line; forming a second region of the programmable material over the first region; the first and second regions being compositionally different from one another; forming a second access line over the second region; wherein the programmable material has two distinguishable and interchangeable memory states, with one of the states being a “SET” state and the other being a “RESET” state; the “SET” state passing greater current between the first and second access lines than the “RESET” state when an electrical field is applied across the programmable material; the “SET” and “RESET” states being interchanged with one another by altering one or both of a concentration of ions and a concentration of ion vacancies in at least one of the first and second regions; wherein the first and second regions together comprise a pn diode in the programmable material in the “SET” state; and providing the ions and/or the ion vacancies in said at least one of the first and second regions.