depositing said {HEAD ~ source material} on a base in the form of {TAIL ~ a precursor film}; and 
depositing said { HEAD ~ source material } on a base in the form of { TAIL ~ a precursor film } ; and
OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH