initially annealing said structure at a high temperature in the range of 900° C. to 1100° C. to overcome any interfacial barrier to diffusion of said impurity species into said structure and to form in {HEAD ~ a surface region} of {TAIL ~ said structure} a surface diffusion profile containing a high concentration of said impurity species, 
initially annealing said structure at a high temperature in the range of 900 ° C. to 1100 ° C. to overcome any interfacial barrier to diffusion of said impurity species into said structure and to form in { HEAD ~ a surface region } of { TAIL ~ said structure } a surface diffusion profile containing a high concentration of said impurity species ,
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH