Finfet device comprising a thermal oxide region positioned between a portion of the fin and a layer of insulating material

Abstract

Disclosed herein are various methods of forming isolation structures on FinFETs and other semiconductor devices, and the resulting devices that have such isolation structures. In one example, the method includes forming a plurality of spaced-apart trenches in a semiconducting substrate, wherein the trenches define a fin for a FinFET device, forming a layer of insulating material in the trenches, wherein the layer of insulating material covers a lower portion of the fin but not an upper portion of the fin, forming a protective material on the upper portion of the fin, and performing a heating process in an oxidizing ambient to form a thermal oxide region on the covered lower portion of the fin.

1 .- 19 . (canceled) 
     
     
         20 . A FinFET device, comprising:
 a fin;   a layer of insulating material positioned proximate opposite sides of said fin, an upper surface of said layer of insulating material being positioned at a level that is below a level of an upper surface of said fin; and   a region of thermal oxide positioned between said fin and said layer of insulating material.   
     
     
         21 . The device of  claim 20 , wherein said region of thermal oxide has a lateral thickness that is less than an entire lateral width of the portion of said fin that extends above said upper surface of said layer of insulating material, wherein said entire lateral width of the portion of said fin is measured at a level corresponding to the level of said upper surface of said layer of insulating material. 
     
     
         22 . The device of  claim 20 , wherein said layer of insulating material is a densified layer of flowable oxide material. 
     
     
         23 . A FinFET device, comprising:
 a fin;   a layer of insulating material positioned on opposite sides of said fin, an upper surface of said layer of insulating material being positioned at a level that is below a level of an upper surface of said fin;   a first region of thermal oxide positioned on a first of said opposite sides of said fin between said fin and said layer of insulating material positioned proximate said first of said opposite sides; and   a second region of thermal oxide positioned on a second of said opposite sides of said fin between said fin and said layer of insulating material positioned proximate said second of said opposite sides.   
     
     
         24 . The device of  claim 23 , wherein said each of said first and second regions of thermal oxide have a lateral thickness that is less than an entire lateral width of the portion of said fin that extends above said upper surface of said layer of insulating material, wherein said entire lateral width of the portion of said fin is measured at a level corresponding to the level of said upper surface of said layer of insulating material. 
     
     
         25 . The device of  claim 23 , wherein said layer of insulating material is a densified layer of flowable oxide material. 
     
     
         26 . A FinFET device, comprising:
 a region of thermal oxide;   a fin positioned above said region of thermal oxide; and   a layer of insulating material positioned adjacent opposite sides of said region of thermal oxide, an upper surface of said layer of insulating material being positioned at a level that is below a level of an upper surface of said fin.   
     
     
         27 . The device of  claim 26 , wherein said region of thermal oxide has a lateral thickness that is substantially the same as an entire lateral width of the portion of said fin that extends above said upper surface of said layer of insulating material, wherein said entire lateral width of the portion of said fin is measured at a level corresponding to the level of said upper surface of said layer of insulating material. 
     
     
         28 . The device of  claim 26 , wherein said layer of insulating material is a densified layer of flowable oxide material. 
     
     
         29 .- 33 . (canceled) 
     
     
         34 . The device of  claim 20 , wherein said fin has a side wall and wherein said region of thermal oxide covers the entire side wall of said fin that is positioned below said upper surface of said layer of insulating material. 
     
     
         35 . The device of  claim 34 , wherein an upper surface of said region of thermal oxide is substantially level with said upper surface of said layer of insulating material. 
     
     
         36 . The device of  claim 23 , wherein:
 said first region of thermal oxide covers the entire first of said opposite sides of said fin that is positioned below said upper surface of said layer of insulating material; and   said second region of thermal oxide covers the entire second of said opposite sides of said fin that is positioned below said upper surface of said layer of insulating material.   
     
     
         37 . The device of  claim 36 , wherein an upper surface of said first region of thermal oxide and an upper surface of said second region of thermal oxide region are substantially level with said upper surface of said layer of insulating material. 
     
     
         38 . The device of  claim 26 , wherein an upper surface of said region of thermal oxide is substantially level with said upper surface of said layer of insulating material.