A three dimensional crossbar array may include a metal layer, and {HEAD ~ an insulator layer} disposed adjacent {TAIL ~ the metal layer} 
A three dimensional crossbar array may include a metal layer , and { HEAD ~ an insulator layer } disposed adjacent { TAIL ~ the metal layer }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL