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;    covering the lower electrode with a protective layer such that said protective layer is formed directly over said lower electrode; and    forming a phase change material over said lower electrode.    
   
   
       2 . The method of  claim 1  further comprising: 
 defining a singulated opening;    forming a cup-shaped phase change material in said opening; and    forming a thermally insulating material in the cup-shaped phase change material.    
   
   
       3 . The method of  claim 2  including defining said phase change material using a planarization process.  
   
   
       4 . The method of  claim 3  including defining said phase change material using a chemical mechanical planarization technique.  
   
   
       5 . The method of  claim 2  including defining a sidewall spacer in said singulated opening.  
   
   
       6 . The method of  claim 5  including defining an electrode in said opening.  
   
   
       7 . The method of  claim 6  including using said sidewall spacer to define the cup-shape of said phase change material.  
   
   
       8 . The method of  claim 6  including forming a base layer over a substrate and forming said lower electrode over said base layer.  
   
   
       9 . The method of  claim 1  including sequentially forming said lower electrode and then said protective layer.  
   
   
       10 . The method of  claim 9  including etching said lower electrode and said protective film using the same mask.  
   
   
       11 - 30 . (Canceled).  
   
   
       31 . The method of  claim 1  including forming the lower electrode and covering the lower electrode with a protective layer in the same chamber.  
   
   
       32 . The method of  claim 31  including depositing the lower electrode and the protective layer in the same deposition chamber.  
   
   
       33 . The method of  claim 32  including depositing the electrode and protective layer in the same deposition chamber without venting back to atmosphere.  
   
   
       34 . The method of  claim 1  including forming the protective layer of an insulator.  
   
   
       35 . The method of  claim 34  including forming the protective layer of a material in the form of silicon nitride.  
   
   
       36 . The method of  claim 35  including forming the silicon nitride in the form of Si 3 N 4 .  
   
   
       37 . A method comprising: forming a protective layer over a lower electrode of a phase change memory.  
   
   
       38 . The method of  claim 37  including forming the lower electrode and covering the lower electrode with a protective layer in the same chamber.  
   
   
       39 . The method of  claim 38  including depositing the lower electrode and the protective layer in the same deposition chamber.  
   
   
       40 . The method of  claim 39  including depositing the electrode and protective layer in the same deposition chamber without venting back to atmosphere.  
   
   
       41 . The method of  claim 37  including forming the protective layer of an insulator.  
   
   
       42 . The method of  claim 41  including forming the protective layer of a material in the form of silicon nitride.  
   
   
       43 . The method of  claim 42  including forming the silicon nitride in the form of Si 3 N 4 .  
   
   
       44 . A method comprising: forming an insulating protective layer over a conductive lower electrode of a phase change memory.  
   
   
       45 . The method of  claim 44  including forming the lower electrode and covering the lower electrode with a protective layer in the same chamber.  
   
   
       46 . The method of  claim 45  including depositing the lower electrode and the protective layer in the same deposition chamber.  
   
   
       47 . The method of  claim 46  including depositing the electrode and protective layer in the same deposition chamber without venting back to atmosphere.  
   
   
       48 . The method of  claim 44  including forming the protective layer of an insulator.  
   
   
       49 . The method of  claim 48  including forming the protective layer of a material in the form of silicon nitride.  
   
   
       50 . The method of  claim 49  including forming the silicon nitride in the form of Si 3 N 4 .