Capacitor constructions and methods of forming

Abstract

A capacitor construction includes a first electrode and a layer between the first electrode and a surface supporting the capacitor construction. The capacitor construction can exhibit a lower RC time constant compared to an otherwise identical capacitor construction lacking the layer. Alternatively, or additionally, the first electrode may contain Si and the layer may limit the Si from contributing to formation of metal silicide material between the first electrode and the supporting surface. The layer may be a nitride layer and may be conductive or insulative. When conductive, the layer may exhibit a first conductivity greater than a second conductivity of the first electrode. The capacitor construction may be used in memory devices.

1 - 41 . (canceled)  
   
   
       42 . A capacitor construction comprising: 
 a metal-containing storage node in a substrate;    a barrier layer over the substrate;    a polysilicon layer over the barrier layer, the polysilicon layer not physically contacting the storage node;    an opening through the polysilicon layer and barrier layer to the storage node;    a first conductive layer over the polysilicon layer and in conductive contact with the storage node through the opening, the first conductive layer being comprised by a first electrode;    a capacitor dielectric over the first electrode; and    a second electrode over the capacitor dielectric.    
   
   
       43 . The capacitor construction of  claim 42  wherein the barrier layer comprises a nitride.  
   
   
       44 . The capacitor construction of  claim 42  wherein the barrier layer is insulative.  
   
   
       45 . The capacitor construction of  claim 42  wherein the barrier layer limits Si of the polysilicon layer from contributing to formation of metal silicide material between the polysilicon layer and the metal-containing storage node.  
   
   
       46 . The capacitor construction of  claim 42  wherein the storage node comprises tungsten.  
   
   
       47 . The capacitor construction of  claim 42  wherein the first conductive layer comprises TiN.  
   
   
       48 . The capacitor construction of  claim 42  wherein the polysilicon layer comprises HSG silicon.  
   
   
       49 . The capacitor construction of  claim 42  wherein the first conductive layer is on the polysilicon layer.  
   
   
       50 . The capacitor construction of  claim 42  wherein the first electrode further comprises the polysilicon layer.  
   
   
       51 . The capacitor construction of  claim 42  wherein the polysilicon layer is undoped.  
   
   
       52 - 63 . (canceled)  
   
   
       64 . A capacitor construction forming method comprising: 
 forming a metal-containing storage node in a substrate;    forming a barrier layer at least over the storage node;    forming a polysilicon layer at least over the storage node and barrier layer, the polysilicon layer not physically contacting the storage node;    forming an opening through the polysilicon layer and barrier layer to the storage node;    forming a first conductive layer over the polysilicon layer and in conductive contact with the storage node through the opening, the first conductive layer being comprised by a first electrode;    forming a capacitor dielectric over the first electrode; and    forming a second electrode over the capacitor dielectric.    
   
   
       65 . The method of  claim 64  wherein the barrier layer comprises a nitride.  
   
   
       66 . The method of  claim 64  wherein the barrier layer is insulative.  
   
   
       67 . The method of  claim 64  wherein the barrier layer limits Si of the polysilicon layer from contributing to formation of metal silicide material between the polysilicon layer and the metal-containing storage node.  
   
   
       68 . The method of  claim 64  wherein the storage node comprises tungsten.  
   
   
       69 . The method of  claim 64  wherein the first conductive layer is formed on the polysilicon layer.  
   
   
       70 . The method of  claim 64  wherein the forming an opening comprises: 
 forming a first opening through the polysilicon layer to the barrier layer;    transforming the polysilicon layer to comprise HSG silicon; and    after the transforming, forming a second opening through the barrier layer to the storage node.    
   
   
       71 - 78 . (canceled)