Methods for Fabricating Resistive Change Element Arrays

Abstract

A method to fabricate a resistive change element array may include depositing a resistive change material over a substrate and forming a first insulating material over the resistive change material. The method may also include etching a trench in the resistive change material and the first insulating material and forming a cavity in a sidewall of the trench by recessing the resistive change material. The method may further include flowing a conductive material in the cavity and depositing a second insulating material in the trench.

What is claimed is: 
     
         1 . A method to fabricate a resistive change element array, said method comprising:
 depositing a resistive change material over a substrate;   forming a first insulating material over said resistive change material;   etching a first trench in said resistive change material and said first insulating material;   forming a cavity in a sidewall of said first trench by recessing said resistive change material;   flowing a conductive material in said cavity; and   depositing a second insulating material in said first trench.   
     
     
         2 . The method of  claim 1 , wherein said resistive change material is a nanotube fabric and said depositing said resistive change material is performed by a spin coating operation. 
     
     
         3 . The method of  claim 1 , further comprising:
 etching a second trench in said resistive change material and said first insulating material; and   depositing a third insulating material in said second trench.   
     
     
         4 . The method of  claim 3 , wherein said recessing said resistive change material results in said resistive change material being divided into first and second portions separated by said third insulating material and said conductive material in said cavity contacts said first and second portions of said resistive change material. 
     
     
         5 . The method of  claim 4 , further comprising:
 forming an opening in said resistive change material and said first insulating material, said opening positioned such that said conductive material in said cavity and said first portion of said resistive change material are between said first trench and said opening; and   flowing a second conductive material in said opening, said second conductive material configured as an electrical contact for said first portion of said resistive change material and insulated from said second portion of said resistive change material.   
     
     
         6 . The method of  claim 5 , wherein said conductive material in said cavity is configured as an electrical contact for said first and second portions of said resistive change material. 
     
     
         7 . The method of  claim 5 , further comprising depositing a second resistive change material over said first insulating material, said second resistive change material being insulated from said conductive material by said first insulating material and said second conductive material configured as an electrical contact for said second resistive change material. 
     
     
         8 . The method of  claim 7 , wherein before depositing said second insulating material said method further comprises:
 forming a second cavity in said sidewall of said first trench by recessing said second resistive change material; and   flowing a third conductive material in said second cavity.   
     
     
         9 . The method of  claim 8 , wherein said forming said second cavity and said forming said cavity are performed by a single chemical etching step and said flowing said conductive material and said flowing said third conductive material are performed by a single deposition step such that said conductive material and said third conductive material are said same conductive material. 
     
     
         10 . The method of  claim 5 , further comprising:
 forming a second opening in said resistive change material and said first insulating material, said second opening positioned such that said conductive material in said cavity and said second portion of said resistive change material are between said first trench and said second opening; and   flowing a third conductive material in said second opening, said third conductive material configured as an electrical contact for said second portion of said resistive change material and insulated from said first portion of said resistive change material.   
     
     
         11 . The method of  claim 10 , wherein said second conductive material and said third conductive material are said same conductive material and said flowing said second conductive material and said third conductive material occurs during a single deposition of said same conductive material. 
     
     
         12 . The method of  claim 1 , further comprising:
 forming an opening in said resistive change material and said first insulating material, said opening positioned such that said conductive material in said cavity is between said first trench and said opening; and   flowing a second conductive material in said opening.   
     
     
         13 . The method of  claim 12 , wherein recessing said resistive change material results in said resistive change material occupying less than one-half of a space between said second insulating material and said second conductive material in a plane that includes said resistive change material, said conductive material, and said second conductive material. 
     
     
         14 . The method of  claim 12 , further comprising:
 forming a second cavity in a sidewall of said opening by recessing said resistive change material by way of said opening;   flowing a third conductive material in said opening; and   after flowing said third conductive material, depositing a selector material in said opening, said selector material deposited before said second conductive material.