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