Semiconductor device structures including a mask material

Abstract

A method for fabricating semiconductor device structures includes forming a non-conformal mask over a surface of a substrate. Non-conformal mask material with a planar or substantially planar upper surface is formed on the surface of the substrate. The planarity or substantial planarity of the non-conformal material eliminates or substantially eliminates distortion in a “mask” formed thereover and, thus, eliminates or substantially eliminates distortion in any mask that is subsequently formed using the pattern of the mask. In some embodiments, mask material of the non-conformal mask does not extend into recesses in the upper surface of the substrate; instead it “bridges” the recesses. Semiconductor device structures that include non-conformal masks and semiconductor device structures that have been fabricated with non-conformal masks are also disclosed.

1 . A semiconductor device structure comprising a mask material on an upper surface of a substrate, the mask material bridging at least one recess in the upper surface of substrate. 
     
     
         2 . The semiconductor device structure of  claim 1 , wherein the mask material has a substantially planar upper surface. 
     
     
         3 . The semiconductor device structure of  claim 1 , further comprising a mask over the mask material and comprising a pattern to be transferred into the mask material. 
     
     
         4 . The semiconductor device structure of  claim 1 , wherein the mask material comprises a pattern to be transferred into a portion of the substrate. 
     
     
         5 . The semiconductor device structure of  claim 1 , wherein the at least one recess in the substrate comprises a first pattern in a portion of the substrate. 
     
     
         6 . The semiconductor device structure of  claim 5 , further comprising a mask over the mask material and comprising a second pattern to be transferred into the mask material, the second pattern oriented so as to cross at least a portion of the first pattern. 
     
     
         7 . The semiconductor device structure of  claim 5 , wherein the mask material comprises a second pattern to be transferred into a portion of the substrate, the second pattern oriented so as to cross at least a portion of the first pattern. 
     
     
         8 . A semiconductor device structure, comprising:
 a substrate;   a first pattern of open recesses defined in a surface of the substrate;   a second pattern of open recesses defined in the surface of the substrate and at least partially crossing and intersecting with the first pattern of open recesses; and   a mask on the surface of the substrate and defining apertures corresponding to the second pattern of open recesses, the mask covering the first pattern of open recesses without substantially extending into the first pattern of open recesses.   
     
     
         9 . The semiconductor device structure of  claim 8 , wherein the mask comprises transparent carbon. 
     
     
         10 . The semiconductor device structure of  claim 8 , wherein the first pattern of open recesses and the second pattern of open recesses at least partially define at least one of a cross-hair cell of a memory device, a diode of a phase-change memory device, or a pseudo silicon-on-insulator structure. 
     
     
         11 . The semiconductor device structure of  claim 1 , wherein the mask material bridges the at least one recess without substantially extending into the at least one recess. 
     
     
         12 . The semiconductor device structure of  claim 1 , wherein the mask material comprises transparent carbon. 
     
     
         13 . The semiconductor device structure of  claim 1 , wherein the mask material comprises silicon nitride doped with hydrogen. 
     
     
         14 . The semiconductor device structure of  claim 1 , wherein the mask material comprises amorphous carbon. 
     
     
         15 . The semiconductor device structure of  claim 1 , wherein the at least one recess has a width within a range of from about 70 nanometers to about 120 nanometers. 
     
     
         16 . A semiconductor device structure, comprising:
 a substrate comprising a plurality of undercut structures defining a plurality of recesses; and   a non-conformal film on the plurality of undercut structures and bridging at least a portion of the plurality of recesses.   
     
     
         17 . The semiconductor device structure of  claim 16 , wherein the plurality of undercut structures comprises a plurality of pseudo silicon-on-insulator structures. 
     
     
         18 . The semiconductor device structure of  claim 17 , wherein the plurality of recesses a first pattern of recesses crossing and communicating with a second pattern of recesses. 
     
     
         19 . The semiconductor device structure of  claim 16 , wherein the non-conformal film has a thickness of about 2000 Angstroms.