Capacitor having a structure capable of restraining deterioration of dielectric film, semiconductor device having the capacitor and method of manufacturing the same

Abstract

Disclosed is a semiconductor device having a structure capable of restraining deterioration of a dielectric film (BSTO) of a capacitor even when annealing is performed in a hydrogen-containing atmosphere. This semiconductor device comprises a plurality of dispersion electrodes (SRO) formed in a dispersed manner above a semiconductor substrate, and a common electrode commonly facing the dispersion electrodes via respective dielectric films (BSTO). This common electrode includes a lower conductive layer (SRO) formed on the dielectric films, a barrier layer (Al 2 O 3 ) formed on the lower conductive layer and an upper conductive layer (Al) formed on the barrier layer.

What is claimed is:  
     
         1 . A semiconductor device comprising: 
 a plurality of dispersion electrodes formed in a dispersed manner above a semiconductor substrate; and    a common electrode commonly facing said dispersion electrodes via respective dielectric films and including a lower conductive layer formed on said dielectric films, a barrier layer formed on said lower conductive layer and an upper conductive layer formed on said barrier layer.    
     
     
         2 . The semiconductor device according to  claim 1 , wherein each of said dispersion electrodes, each of said dielectric films and said lower conductive layer constitute a first capacitor, said lower conductive layer, said barrier layer and said upper conductive layer constitute a second capacitor, and a capacitance of said second capacitor is greater than that of said first capacitor.  
     
     
         3 . The semiconductor device according to  claim 1 , wherein said barrier layer is formed of a metal oxide.  
     
     
         4 . The semiconductor device according to  claim 3 , wherein said metal oxide contains at least one of Ta, Al, W, Cu, Ti, Co, Nb, Ru and Ir.  
     
     
         5 . The semiconductor device according to  claim 1 , wherein said barrier layer is formed of a silicon nitride.  
     
     
         6 . The semiconductor device according to  claim 1 , wherein said dielectric films are formed of an oxide.  
     
     
         7 . The semiconductor device according to  claim 6 , wherein said oxide contains at least one of (Ba,Sr)TiO 3 , BaTiO 3 , SrTiO 3 , Ta 2 O 5 , Pb(Zr,Ti)O 3 , Pb(Nb,Ti)O 3 , PbZrO 3 , LiNbO 3 , SrBi 2 Ta 2 O 9 , SrBi 2 (Ta,Nb) 2 O 9  and Bi 4 Ti 3 O 13 .  
     
     
         8 . The semiconductor device according to  claim 1 , wherein said lower conductive layer contains at least one of Pt, Ru, Re, Os, Rh, Ir, Fe, Mn, Cr, Co, Ni and Ti.  
     
     
         9 . The semiconductor device according to  claim 1 , wherein said upper conductive layer contains at least one of Al, W, Cu, Ti, Co, Ta and Nb.  
     
     
         10 . A semiconductor device comprising: 
 one electrode formed above a semiconductor substrate; and    an opposing electrode facing said one electrode via a dielectric film and including a lower conductive layer formed on said dielectric film, a barrier layer formed on said lower conductive layer and an upper conductive layer formed on said barrier layer.    
     
     
         11 . The semiconductor device according to  claim 10 , wherein an electrical resistivity of said upper conductive layer is lower than those of said lower conductive layer and said barrier layer.  
     
     
         12 . The semiconductor device according to  claim 10 , wherein said barrier layer is formed of a metal oxide.  
     
     
         13 . The semiconductor device according to  claim 12 , wherein said metal oxide contains at least one of Ta, Al, W, Cu, Ti, Co, Nb, Ru and Ir.  
     
     
         14 . The semiconductor device according to  claim 10 , wherein said barrier layer is formed of a silicon nitride.  
     
     
         15 . The semiconductor device according to  claim 10 , wherein said dielectric film is formed of an oxide.  
     
     
         16 . The semiconductor device according to  claim 15 , wherein said oxide contains at least one of (Ba,Sr)TiO 3 , BaTiO 3 , SrTiO 3 , Ta 2 O 5 , Pb(Zr,Ti)O 3 , Pb(Nb,Ti)O 3 , PbZrO 3 , LiNbO 3 , SrBi 2 Ta 2 O 9 , SrBi 2 (Ta,Nb) 2 O 9  and Bi 4 Ti 3 O 13 .  
     
     
         17 . The semiconductor device according to  claim 10 , wherein said lower conductive layer contains at least one of Pt, Ru, Re, Os, Rh, Ir, Fe, Mn, Cr, Co, Ni and Ti.  
     
     
         18 . The semiconductor device according to  claim 10 , wherein said upper conductive layer contains at least one of Al, W, Cu, Ti, Co, Ta and Nb.  
     
     
         19 . A semiconductor device comprising: 
 a capacitor structure formed above a semiconductor substrate and including one electrode and an opposing electrode facing said one electrode via a dielectric film; and    a barrier layer formed around said capacitor structure and substantially covering said capacitor structure.    
     
     
         20 . The semiconductor device according to  claim 19 , wherein said barrier layer is formed of a metal oxide.  
     
     
         21 . The semiconductor device according to  claim 20 , wherein said metal oxide contains at least one of Ta, Al, W, Cu, Ti, Co, Nb, Ru and Ir.  
     
     
         22 . The semiconductor device according to  claim 19 , wherein said barrier layer is formed of a silicon nitride.  
     
     
         23 . The semiconductor device according to  claim 19 , wherein said dielectric film is formed of an oxide.  
     
     
         24 . The semiconductor device according to  claim 23 , wherein said oxide contains at least one of (Ba,Sr)TiO 3 , BaTiO 3 , SrTiO 3 , Ta 2 O 5 , Pb(Zr,Ti)O 3 , Pb(Nb,Ti)O 3 , PbZrO 3 , LiNbO 3 , SrBi 2 Ta 2 O 9 , SrBi 2 (Ta,Nb) 2 O 9  and Bi 4 Ti 3 O 13 .  
     
     
         25 . A semiconductor device comprising: 
 a metal oxide formed on a semiconductor substrate;    a first conductive film formed on said metal oxide; and    a second conductive film facing said first conductive film via a dielectric film.    
     
     
         26 . The semiconductor device according to  claim 25 , wherein said metal oxide contains at least one of Ta, Al, W, Cu, Ti, Co, Nb, Ru and Ir.  
     
     
         27 . The semiconductor device according to  claim 25 , wherein said dielectric film is formed of an oxide.  
     
     
         28 . The semiconductor device according to  claim 27 , wherein said oxide contains at least one of (Ba,Sr)TiO 3 , BaTiO 3 , SrTiO 3 , Ta 2 O 5 , Pb(Zr,Ti)O 3 , Pb(Nb,Ti)O 3 , PbZrO 3 , LiNbO 3 , SrBi 2 Ta 2 O 9 , SrBi 2 (Ta,Nb) 2 O 9  and Bi 4 Ti 3 O 3 .  
     
     
         29 . A semiconductor device comprising: 
 memory cells each having a cell capacitor which includes a storage electrode and a plate electrode facing said storage electrode via a dielectric film;    a circuit for generating a potential to be applied to said plate electrode; and    a capacitor connected in series between an output terminal of said circuit and said plate electrode.    
     
     
         30 . A method of manufacturing a semiconductor device comprising the steps of: 
 forming one electrode above a semiconductor substrate;    forming a dielectric film on said one electrode;    forming a lower conductive layer on said dielectric film;    forming a barrier layer on said lower conductive layer;    forming an upper conductive layer on said barrier layer; and    processing said upper conductive layer, said barrier layer and said lower conductive layer to form an opposing electrode including said upper conductive layer, said barrier layer and said lower conductive layer.