Phase Change Material Memory Device

Abstract

A lower electrode may be covered by a protective film to reduce the exposure of the lower electrode to subsequent processing steps or the open environment. As a result, materials that may have advantageous properties as lower electrodes may be utilized despite the fact that they may be sensitive to subsequent processing steps or the open environment.

1 . A method comprising:
 forming a lower electrode and a protective layer over said lower electrode of a phase change memory in the same deposition chamber without venting back to atmosphere.   
     
     
         2 . The method of  claim 1  including forming the protective layer of an insulator. 
     
     
         3 . The method of  claim 2  including forming the protective layer of a material in the form of silicon nitride. 
     
     
         4 . The method of  claim 3  including forming the silicon nitride in the form of Si 3 N 4 . 
     
     
         5 . The method of  claim 4  including etching an opening through said lower electrode and said protective layer. 
     
     
         6 . The method of  claim 5  including forming an insulator over said opening in said lower electrode and said protective layer. 
     
     
         7 . The method of  claim 6  including forming an etched hole through said insulator down to said protective layer. 
     
     
         8 . The method of  claim 7  including forming sidewall spacers in said hole. 
     
     
         9 . The method of  claim 8  including using said sidewall spacers to etch a hole through said protective layer. 
     
     
         10 . The method of  claim 1  including depositing a chalcogenide on the exposed portion of said lower electrode. 
     
     
         11 . The method of  claim 1  including depositing said lower electrode in a deposition chamber and then depositing the protective layer directly on said lower electrode in said chamber without venting the chamber. 
     
     
         12 . A method comprising:
 depositing a lower electrode in a deposition chamber;   depositing in said deposition chamber a protective layer directly on said lower electrode without venting the chamber; and   depositing a chalcogenide through an opening in said protective layer to contact said lower electrode.   
     
     
         13 . The method of  claim 12  including forming the protective layer of an insulator. 
     
     
         14 . The method of  claim 13  including forming the protective layer of a material in the form of silicon nitride. 
     
     
         15 . The method of  claim 14  including forming the silicon nitride in the form of Si 3 N 4 . 
     
     
         16 . The method of  claim 15  including etching an opening through said lower electrode and said protective layer. 
     
     
         17 . The method of  claim 16  including forming an insulator over said opening in said lower electrode and said protective layer. 
     
     
         18 . The method of  claim 17  including forming an etched hole through said insulator down to said protective layer. 
     
     
         19 . The method of  claim 18  including forming sidewall spacers in said hole. 
     
     
         20 . The method of  claim 19  including using said sidewall spacers to etch a hole through said protective layer. 
     
     
         21 . The method of  claim 12  including depositing a chalcogenide on the exposed portion of said lower electrode.