Semiconductor constructions

Abstract

The invention includes methods of forming openings extending through electrically insulative layers to electrically conductive materials. In an exemplary aspect, a substrate is provided which supports a stack and an electrical node. The stack comprises an electrically insulative cap over an electrically conductive material. An electrically insulative layer is formed over the stack and over the electrical node. A first etch is utilized to etch through the electrically insulative layer to the electrical node and to the electrically insulative cap. The first etch etches partially into the electrically insulative cap but does not etch entirely through the electrically insulative cap. A second etch is utilized after the first etch to etch entirely through the electrically insulative cap to the electrically conductive material of the stack.

1 - 48 . (canceled)  
   
   
       49 . A semiconductor construction, comprising: 
 a monocrystalline silicon base;    a stack supported by the base; the stack comprising an electrically insulative cap over an electrically conductive material; the electrically insulative cap of the stack having a thin central region laterally sandwiched between a pair of thicker peripheral regions, the thin central region joining to the thicker peripheral regions at locations over the electrically conductive material; the electrically insulative cap being of a first composition;    an electrically insulative material over the stack; the electrically insulative material being of a second composition different from the first composition; and    an electrical interconnect extending through both the electrically insulative material and the electrically insulative cap to electrically connect with the electrically conductive material of the stack; the portion of the electrical interconnect which extends through the electrically insulative cap being entirely within the thin central region of the electrically insulative cap.    
   
   
       50 . The construction of  claim 49  wherein the first composition consists of silicon nitride and the second composition comprises a silicon oxide.  
   
   
       51 . The construction of  claim 49  wherein the electrically insulative cap is part of an electrically insulative shell that extends along sidewalls of the electrically conductive material as well over the electrically conductive material; with an entirety of the shell being of the first composition.  
   
   
       52 . The construction of  claim 49  wherein the thin central region of the electrically insulative cap joins to the thicker peripheral regions through steps having approximately right angles at the locations where the central region meets the peripheral regions.  
   
   
       53 . The construction of  claim 49  wherein the interconnect does not extend to laterally over the thicker peripheral portions of the electrically insulative cap.  
   
   
       54 . A semiconductor construction, comprising: 
 a monocrystalline silicon base;    a stack supported by the base; the stack comprising an electrically insulative cap over an electrically conductive material; the electrically insulative cap of the stack having a thin central region laterally sandwiched between a pair of thicker peripheral regions, the thin central region joining to the thicker peripheral regions at steps, said steps being directly over the electrically conductive material of the stack;    an electrically conductive pillar supported by the base, the pillar having an uppermost surface and a lateral periphery;    an electrically conductive cap on the electrically conductive pillar and having a lateral periphery extending outwardly beyond the lateral periphery of the electrically conductive pillar, the electrically conductive cap and electrically conductive pillar differing in composition relative to one another;    an electrically insulative material over the stack and over the electrically conductive cap; and    an electrical interconnect extending through both the electrically insulative material and the electrically insulative cap to electrically connect with the electrically conductive material of the stack; the portion of the electrical interconnect which extends through the electrically insulative cap being entirely within the thin central region of the electrically insulative cap.    
   
   
       55 . The construction of  claim 54  wherein the electrically conductive cap comprises tungsten and the electrically conductive pillar comprises conductively-doped silicon.  
   
   
       56 . The construction of  claim 54  wherein the electrically insulative cap comprises silicon nitride.  
   
   
       57 . The construction of  claim 54  wherein the electrically insulative cap consists essentially of silicon nitride.  
   
   
       58 . The construction of  claim 54  wherein the electrically insulative cap consists of silicon nitride.  
   
   
       59 . The construction of  claim 54  further comprising at least one transistor gate between the conductive pillar and the stack.  
   
   
       60 . The construction of  claim 54  wherein the conductive material of the stack is a part of a wordline and the electrically conductive cap is part of a bitline.