{TAIL ~ The precursor reacts} under the second conditions to form the desired material, and {HEAD ~ at least some} of the desired material forms a layer on the substrate 
{ TAIL ~ The precursor reacts } under the second conditions to form the desired material , and { HEAD ~ at least some } of the desired material forms a layer on the substrate
TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH