Programmable resistive memory cell with sacrificial metal

Abstract

Programmable metallization memory cells include an electrochemically active electrode and an inert electrode and an ion conductor solid electrolyte material between the electrochemically active electrode and the inert electrode. A sacrificial metal is disposed between the electrochemically active electrode and the inert electrode. The sacrificial metal has a more negative standard electrode potential than the filament forming metal

What is claimed is: 
     
         1 . A programmable metallization memory cell comprising:
 an electrochemically active electrode and an inert electrode, the electrochemically active electrode comprising filament forming metal;   an ion conductor solid electrolyte material between the electrochemically active electrode and the inert electrode; and   a sacrificial metal disposed between the ion conductor solid electrolyte material and the inert electrode, the sacrificial metal having a more negative standard electrode potential than the filament forming metal.   
     
     
         2 . The programmable metallization memory cell of  claim 1  wherein the sacrificial metal has a smaller atomic radius than the filament forming metal. 
     
     
         3 . The programmable metallization memory cell of  claim 1  wherein the filament forming metal is silver and the sacrificial metal is chromium, nickel or zinc. 
     
     
         4 . The programmable metallization memory cell of  claim 1  wherein sacrificial metal donates electrons to the filament forming metal to stabilize filaments formed by the filament forming metal, the filaments electrically connecting the electrochemically active electrode and the inert electrode. 
     
     
         5 . The programmable metallization memory cell of  claim 1  wherein the ion conductor solid electrolyte material comprises a chalcogenide material 
     
     
         6 . The programmable metallization memory cell of  claim 1  wherein the sacrificial metal forms a sacrificial metal layer on either the electrochemically active electrode or the inert electrode and the layer having a thickness of less than 50 nanometers. 
     
     
         7 . The programmable metallization memory cell of  claim 1  wherein the sacrificial metal is dispersed within the ion conductor solid electrolyte material. 
     
     
         8 . The programmable metallization memory cell of  claim 1  wherein the sacrificial metal is in the form of metal ions. 
     
     
         9 . A programmable metallization memory cell comprising:
 an electrochemically active electrode and an inert electrode, the electrochemically active electrode comprising filament forming metal;   an ion conductor solid electrolyte material between the electrochemically active electrode and the inert electrode; and   sacrificial metal particles dispersed within the ion conductor solid electrolyte material, the sacrificial metal having a more negative standard electrode potential than the filament forming metal.   
     
     
         10 . The programmable metallization memory cell of  claim 9  wherein the sacrificial metal has a smaller atomic radius than the filament forming metal. 
     
     
         11 . The programmable metallization memory cell of  claim 9  wherein the filament forming metal is silver and the sacrificial metal is chromium, nickel or zinc. 
     
     
         12 . The programmable metallization memory cell of  claim 9  wherein sacrificial metal donates electrons to the filament forming metal to stabilize filaments formed by the filament forming metal, the filaments electrically connecting the electrochemically active electrode and the inert electrode. 
     
     
         13 . The programmable metallization memory cell of  claim 9  wherein the ion conductor solid electrolyte material comprises a chalcogenide material. 
     
     
         14 . A method comprising:
 depositing an ion conductor solid electrolyte layer on an inert electrode;   depositing a sacrificial metal layer on the ion conductor solid electrolyte layer;   depositing an electrochemically active electrode on the a sacrificial metal layer to form a programmable metallization memory cell, the electrochemically active electrode comprising filament forming metal and the sacrificial metal particles have a more negative standard electrode potential than the filament forming metal.   
     
     
         15 . The method of  claim 14 , wherein the sacrificial metal layer has a thickness of less than 50 nanometers. 
     
     
         16 . The method of  claim 14 , wherein the sacrificial metal layer is formed of particles having a smaller atomic radius than the filament forming metal. 
     
     
         17 . The method of  claim 14  wherein the filament forming metal is silver and the sacrificial metal layer is chromium, nickel or zinc. 
     
     
         18 . The method of  claim 14  wherein sacrificial metal donates electrons to the filament forming metal to stabilize filaments formed by the filament forming metal, the filaments electrically connecting the electrochemically active electrode and the inert electrode. 
     
     
         19 . The method of  claim 14  wherein the ion conductor solid electrolyte material comprises a chalcogenide material. 
     
     
         20 . The method of  claim 14  wherein the filament forming metal is silver and the sacrificial metal particles are chromium or nickel.