{HEAD ~ a second series} of laser drilled wells, having a second spacing are made in {TAIL ~ the substrate material} to form the remaining portion of the perimeter of the irregular shaped substrate 
are made in
{ HEAD ~ a second series } of laser drilled wells , having a second spacing are made in { TAIL ~ the substrate material } to form the remaining portion of the perimeter of the irregular shaped substrate
HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH REL REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH