Post-fabrication self-aligned initialization of integrated devices

Abstract

A phase change memory (PCM) cell that includes a first electrode contacting a first layer of material having a first chemical composition. The PCM cell also includes a second layer of material having a second chemical composition and a second electrode contacting the first layer of material or the second layer of material. The PCM cell is configured for receiving at least one electrical current pulse flowing from the first electrode to the second electrode to locally heat a region of the first layer and the second layer to cause at least one of inter-diffusion and liquid mixing of the first layer of material and the second layer of material, resulting in a self-aligned region of phase change material having a chemical composition that is a mixture of the first chemical composition and the second chemical composition.

What is claimed is: 
     
         1 . A phase change memory (PCM) cell comprising:
 a first electrode contacting a first layer of material having a first chemical composition;   a second layer of material having a second chemical composition; and   a second electrode contacting the first layer of material or the second layer of material;   the PCM cell configured for receiving at least one electrical current pulse flowing from the first electrode to the second electrode to locally heat a region of the first layer and the second layer to cause at least one of inter-diffusion and liquid mixing of the first layer of material and the second layer of material, resulting in a self-aligned region of phase change material having a chemical composition that is a mixture of the first chemical composition and the second chemical composition.   
     
     
         2 . The PCM cell of  claim 1 , wherein the first layer of material is an amorphous threshold switching material having high electrical resistivity at low electric field strength and substantially reduced electrical resistivity at electric field strengths above a threshold. 
     
     
         3 . The PCM cell of  claim 1 , wherein the first layer of material is an insulator and the second layer of material is the phase change material, or the first layer of material is the phase change material and the second layer of material is an insulator. 
     
     
         4 . The PCM cell of  claim 1 , wherein the PCM cell is characterized by a parallel path memory cell structure. 
     
     
         5 . The PCM cell of  claim 1 , wherein the PCM cell is characterized by a vertical path memory cell structure. 
     
     
         6 . A design structure tangibly embodied in a machine readable medium for designing, manufacturing, or testing an integrated circuit, the design structure having a substantially planar surface, the design structure comprising:
 a phase change memory (PCM) cell comprising:   a first electrode contacting a first layer of material having a first chemical composition;   a second layer of material having a second chemical composition; and   a second electrode contacting the first layer of material or the second layer of material;   the PCM cell configured for receiving at least one electrical current pulse flowing from the first electrode to the second electrode to locally heat a region of the first layer and the second layer to cause at least one of inter-diffusion and liquid mixing of the first layer of material and the second layer of material, resulting in a self-aligned region of phase change material having a chemical composition that is a mixture of the first chemical composition and the second chemical composition.   
     
     
         7 . The design structure of  claim 6 , wherein the PCM cell is characterized by one of a parallel path memory cell structure and a vertical path memory cell structure.