Methods of forming strained semiconductor channels

Abstract

In various method embodiments, a device region in a semiconductor substrate and isolation regions adjacent to the device region are defined. The device region has a channel region and the isolation regions have strain-inducing regions laterally adjacent to the channel regions. The channel region is strained with a desired strain for carrier mobility enhancement, where at least one ion type is implanted with an energy resulting in a peak implant in the strain-inducing regions of the isolation regions. Other aspects and embodiments are provided herein.

1 . A semiconductor structure, comprising:
 a device region and isolation regions adjacent to the device region;   the device region including a first source/drain region, a second source/drain region, and a channel region between the first source/drain region and the second source drain region;   the isolation regions having strain-inducing regions laterally adjacent to the channel region and having a depth generally corresponding to a depth of the channel region; and   the channel region including a strain induced by the strain-inducing regions in the isolation regions.   
     
     
         2 . The structure of  claim 1 , wherein the strain-inducing regions include implanted helium ions. 
     
     
         3 . The structure of  claim 1 , wherein the strain-inducing regions include nanocavities. 
     
     
         4 . The structure of  claim 3 , wherein the strain-inducing regions include an oxide. 
     
     
         5 . The structure of  claim 4 , wherein the oxide includes silicon dioxide. 
     
     
         6 . The structure of  claim 4 , wherein the strain-inducing regions include an oxide formed using implanted oxygen ions. 
     
     
         7 . The structure of  claim 1 , wherein the strain-inducing regions includes implanted argon ions. 
     
     
         8 . The structure of  claim 1 , wherein the strain-inducing regions includes implanted hydrogen ions. 
     
     
         9 . The structure of  claim 1 , wherein the strain-inducing regions includes implanted argon ions and implanted hydrogen ions. 
     
     
         10 . The structure of  claim 1 , wherein the channel region includes a tensile strain. 
     
     
         11 . The structure of  claim 10 , wherein the tensile strain is within a range of approximately 0.75% to approximately 1.5%. 
     
     
         12 . The structure of  claim 1 , wherein the channel region includes a compressive strain. 
     
     
         13 . The structure of  claim 12 , wherein the compressive strain is within a range of approximately 0.2% to approximately 1.0%. 
     
     
         14 . The structure of  claim 1 , wherein the strain is a predominantly uniaxial strain. 
     
     
         15 . The structure of  claim 1 , wherein the strain is a predominantly biaxial strain. 
     
     
         16 . The structure of  claim 1 , further comprising an epitaxial semiconductor layer on the device region and the isolation region. 
     
     
         17 . A semiconductor structure, comprising:
 a p-channel device, including a p-channel device region and p-channel isolation regions on opposing sides of the p-channel device region, the p-channel device region including first and second source/drain regions and a p-channel region between the first and second source drain regions, the p-channel isolation regions having strain-inducing regions laterally adjacent to the p-channel region and having a depth generally corresponding to a depth of the p-channel region, and the p-channel region including a compressive strain induced by the strain-inducing regions in the p-channel isolation regions; and   an n-channel device, including an n-channel device region and n-channel isolation regions on opposing sides of the n-channel device region, the n-channel device region including first and second source/drain regions and a n-channel region between the first and second source drain regions, the n-channel isolation regions having strain-inducing regions laterally adjacent to the n-channel region and having a depth generally corresponding to a depth of the n-channel region, and the n-channel region including a tensile strain induced by the strain-inducing regions in the n-channel isolation regions.   
     
     
         18 . The structure of  claim 17 , wherein the strain-inducing regions of the n-channel isolation regions and the p-channel isolation regions include implanted helium ions. 
     
     
         19 . The structure of  claim 18 , wherein the strain-inducing regions of the p-channel isolation regions include an oxide formed using implanted oxygen ions. 
     
     
         20 . The structure of  claim 18 , wherein the strain-inducing regions of the n-channel isolation regions include implanted argon ions. 
     
     
         21 . The structure of  claim 20 , wherein the strain-inducing regions of the n-channel isolation regions include implanted hydrogen ions. 
     
     
         22 . The structure of  claim 17 , further comprising an epitaxial silicon layer on the p-channel isolation regions and the n-channel isolation regions. 
     
     
         23 . The structure of  claim 22 , wherein the strain-inducing regions of the p-channel isolation regions include implanted helium ions. 
     
     
         24 . The structure of  claim 22 , wherein the strain-inducing regions of the n-channel isolation regions include implanted argon ions. 
     
     
         25 . The structure of  claim 22 , wherein the strain-inducing regions of the n-channel isolation regions include implanted hydrogen ions. 
     
     
         26 . A semiconductor structure, comprising:
 a device region;   a first isolation trench on a first side of the device region and a second isolation trench on a second side of the device region, and isolation regions adjacent to the device region;   the device region including a first source/drain region, a second source/drain region, and a channel region between the first source/drain region and the second source drain region;   each of the first and second isolation trenches having a strain-inducing region laterally adjacent to the channel region, the strain-inducing regions having a depth generally corresponding to a depth of the channel region, the isolation trenches having a stepped cross-sectional profile, wherein a step in the profile of the isolation trenches corresponds to a bottom of the strain-inducing region; and   the channel region including a strain induced by the strain-inducing regions in the isolation regions.   
     
     
         27 . The structure of  claim 26 , wherein the step in the profile reflects expanded strain-inducing regions that induce a compressive strain in the channel region. 
     
     
         28 . The structure of  claim 27 , wherein the compressive strain includes a strain within a range of approximately 0.2% to approximately 1.0%. 
     
     
         29 . The structure of  claim 26 , wherein the step in the profile reflects contracted strain-inducing regions that induce a tensile strain in the channel region. 
     
     
         30 . The structure of  claim 29 , wherein the tensile strain includes a strain greater than approximately 0.5%. 
     
     
         31 . The structure of  claim 29 , wherein the tensile strain includes a strain within a range of approximately 0.75% to approximately 1.5%.