The spacer preferably comprises a material selected from {TAIL ~ the group} comprising refractory metal silicides or their associated nitrides, such as, for example, titanium silicide, {HEAD ~ titanium nitride}, and cobalt silicide 
The spacer preferably comprises a material selected from { TAIL ~ the group } comprising refractory metal silicides or their associated nitrides , such as , for example , titanium silicide , { HEAD ~ titanium nitride } , and cobalt silicide
OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH