Preferably, the nozzle, channel and {HEAD ~ recess} are etched from the silicon substrate by {TAIL ~ reactive ion etching} and other standard semiconductor processing techniques 
are etched by
Preferably , the nozzle , channel and { HEAD ~ recess } are etched from the silicon substrate by { TAIL ~ reactive ion etching } and other standard semiconductor processing techniques
OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD REL REL OTH OTH OTH OTH REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH