Finfet semiconductor devices with stressed layers

Abstract

A device includes at least one fin defined in a semiconductor substrate, a raised isolation structure surrounding and laterally spaced apart from the fin, and a gate structure extending across and positioned around a first portion of the fin. A buried fin contact structure is positioned inside of the raised isolation structure and extends across, is positioned around, and conductively contacts a second portion of the fin. An upper surface of the buried fin contact structure is positioned level with or below an upper surface of the raised isolation structure. A stress-inducing material layer is positioned on and in contact with the upper surface of the buried fin contact structure, an insulating material layer is positioned above the stress-inducing material layer and the raised isolation structure, and a contact structure extends through at least the insulating and stress-inducing material layers and conductively contacts the buried fin contact structure.

What is claimed: 
     
         1 . A device, comprising:
 at least one fin defined in a semiconductor substrate;   a raised isolation structure surrounding and laterally spaced apart from said at least one fin;   a gate structure extending across and positioned around a first portion of said at least one fin;   a buried fin contact structure positioned inside of said raised isolation structure, wherein said buried fin contact structure extends across, is positioned around, and conductively contacts a second portion of said at least one fin, and wherein an upper surface of said buried fin contact structure is positioned level with or below an upper surface of said raised isolation structure;   a stress-inducing material layer positioned on and in contact with said upper surface of said buried fin contact structure;   an insulating material layer positioned above said stress-inducing material layer and said raised isolation structure; and   a contact structure that extends through at least said insulating material layer and said stress-inducing material layer and conductively contacts said buried fin contact structure.   
     
     
         2 . The device of  claim 1 , wherein at least a portion of an outer perimeter surface of said buried fin contact structure contacts at least a portion of an interior perimeter surface of said raised isolation structure. 
     
     
         3 . The device of  claim 2 , wherein a portion of said outer perimeter surface contacts a sidewall spacer positioned adjacent to said gate structure. 
     
     
         4 . The device of  claim 1 , wherein said contact structure is a post-type contact structure. 
     
     
         5 . The device of  claim 1 , wherein said stress-inducing material layer contacts substantially an entirety of said upper surface of said buried fin contact structure. 
     
     
         6 . The device of  claim 1 , wherein said gate structure is a replacement gate structure comprising a high-k gate dielectric material and a work function adjusting metal gate electrode material. 
     
     
         7 . The device of  claim 1 , wherein said raised isolation structure has a recessed surface positioned under said gate structure, said recessed surface being positioned at a height level that is below a height level of said upper surface of said raised isolation structure. 
     
     
         8 . The device of  claim 1 , wherein said upper surface of said raised isolation structure is positioned at a height level that is above a height level of an upper surface of said at least one fin. 
     
     
         9 . The device of  claim 1 , wherein a first portion of said buried fin contact structure is positioned between a sidewall of said at least one fin and a sidewall of said raised isolation structure. 
     
     
         10 . The device of  claim 9 , wherein said at least one fin comprises a first fin and a second fin, and wherein a second portion of said buried fin contact structure is positioned between adjacent sidewalls of said first and second fins. 
     
     
         11 . The device of  claim 1 , wherein said buried fin contact structure is a first buried fin contact structure, said second portion of said at least one fin is a source-side portion of said at least one fin, and said contact structure is a first contact structure, the device further comprising:
 a second buried fin contact structure positioned inside of said raised isolation structure, wherein said second buried fin contact structure extends across, is positioned around, and conductively contacts a drain-side portion of said at least one fin, wherein an upper surface of said second buried fin contact structure is positioned level with or below said upper surface of said raised isolation structure, and wherein a portion of said stress-inducing material layer is positioned on and in contact with said upper surface of said second buried fin contact structure; and   a second contact structure that extends through at least said insulating material layer and said stress-inducing material layer and conductively contacts said second buried fin contact structure.   
     
     
         12 . A device, comprising:
 at least one fin defined in a semiconductor substrate;   a raised isolation structure with a recess formed therein, wherein said recess has an upper surface, a bottom surface that is positioned below said upper surface, and an interior perimeter surface;   a gate structure positioned around at least a portion of said at least one fin;   a plurality of spaced-apart buried fin contact structures positioned within said recess, wherein each of said buried fin contact structures is positioned on opposite sides of said gate structure and wherein each of said buried fin contact structures is conductively coupled to said at least one fin and has a substantially planar upper surface that is positioned level with or below said upper surface of said raised isolation structure;   a stress-inducing material layer positioned on and in contact with said substantially planar upper surface of each of said buried fin contact structures;   at least one layer of insulating material positioned above said stress-inducing material layer, said plurality of buried fin contact structures, and said raised isolation structure; and   a plurality of source/drain contact structures that extend through said at least one layer of insulating material and through said stress-inducing material layer, wherein each of said source/drain contact structures is conductively coupled to one of said plurality of buried fin contact structures.   
     
     
         13 . The device of  claim 12 , wherein at least a portion of an outer perimeter surface of each of said buried fin contact structures contacts at least a portion of said interior perimeter surface of said recess in said raised isolation structure. 
     
     
         14 . The device of  claim 13 , wherein a portion of said outer perimeter surface of each of said buried fin contact structures contacts a sidewall spacer positioned adjacent to opposite sides of said gate structure. 
     
     
         15 . The device of  claim 12 , wherein said plurality of source/drain contact structures are post-type source/drain contact structures. 
     
     
         16 . The device of  claim 12 , wherein said stress-inducing material layer contacts substantially an entirety of said upper surface of each of said plurality of buried fin contact structures. 
     
     
         17 . The device of  claim 12 , wherein said gate structure is a replacement gate structure comprising a high-k gate dielectric material and a work function adjusting metal gate electrode material. 
     
     
         18 . The device of  claim 12 , wherein said raised isolation structure has a recessed surface positioned under said gate structure, said recessed surface being positioned at a height level that is below a height level of said upper surface of said raised isolation structure. 
     
     
         19 . The device of  claim 12 , wherein a first portion of each of said buried fin contact structures is positioned between a sidewall of said at least one fin and a sidewall of said raised isolation structure. 
     
     
         20 . The device of  claim 12 , wherein said at least one fin comprises a first fin and a second fin, and wherein a second portion of each of said buried fin contact structures is positioned between adjacent sidewalls of said first and second fins.