Nonvolatile memory device

Abstract

A nonvolatile memory device, including a lower electrode on a semiconductor substrate, a phase change material pattern on the lower electrode, an adhesion pattern on the phase change material pattern and an upper electrode on the adhesion pattern, wherein the adhesion pattern includes a conductor including nitrogen.

1 . A nonvolatile memory device, comprising:
 a lower electrode on a semiconductor substrate;   a phase change material pattern on the lower electrode;   an adhesion pattern on the phase change material pattern; and   an upper electrode on the adhesion pattern,   wherein the adhesion pattern includes a conductor including nitrogen.   
     
     
         2 . The nonvolatile memory device as claimed in  claim 1 , wherein the adhesion pattern and the upper electrode each independently include a metal nitride layer or a metal oxynitride layer, and a ratio of metal to nitrogen in the metal nitride or oxynitride layer in the adhesion pattern is different from a ratio of metal to nitrogen in the metal nitride or oxynitride layer in the upper electrode. 
     
     
         3 . The nonvolatile memory device as claimed in  claim 1 , wherein the adhesion pattern includes a metal nitride layer, and a ratio of metal to nitrogen in the metal nitride layer is about 1:0.95 to about 1:1.03. 
     
     
         4 . The nonvolatile memory device as claimed in  claim 3 , wherein the metal of the metal nitride layer includes at least one of titanium, tantalum, molybdenum, and tungsten. 
     
     
         5 . The nonvolatile memory device as claimed in  claim 1 , wherein the upper electrode includes at least one of metal, metal nitride, and metal oxynitride. 
     
     
         6 . The nonvolatile memory device as claimed in  claim 5 , wherein the upper electrode includes a metal including at least one of Ti, Ta, Mo, W, TiW, TiSi, and TaSi. 
     
     
         7 . The nonvolatile memory device as claimed in  claim 5 , wherein the upper electrode includes a metal nitride including at least one of TiN, TaN, WN, MoN, NbN, TiSiN, TiAlN, ZrSiN, WSiN, WBN, ZrAlN, MoSiN, TaSiN, and TaAlN. 
     
     
         8 . The nonvolatile memory device as claimed in  claim 5 , wherein the upper electrode includes a metal oxynitride including at least one of TiON, TiAlON, WON, and TaON. 
     
     
         9 . The nonvolatile memory device as claimed in  claim 1 , wherein the phase change material pattern includes at least one of Ge—Sb—Te, Sb—Te, As—Sb—Te, and Sb—Se. 
     
     
         10 . The nonvolatile memory device as claimed in  claim 9 , wherein the phase change material pattern further includes at least one metal. 
     
     
         11 . The nonvolatile memory device as claimed in  claim 1 , wherein the lower electrode includes at least one of metal nitride, metal, metal oxynitride, silicide, and conductive carbon. 
     
     
         12 . The nonvolatile memory device as claimed in  claim 11 , wherein the lower electrode includes at least one of Ti, Ta, Mo, W, TiN, TaN, WN, MoN, NbN, TiSiN, TiAlN, ZrSiN, WSiN, WBN, ZrAlN, MoSiN, TaSiN, TaAlN, TiW, TiSi, TaSi, TiON, TiAlON, WON, and TaON. 
     
     
         13 - 24 . (canceled)