{HEAD ~ The method} 13, wherein {TAIL ~ a number} of masking steps used for forming the crossbar array is independent of a number of metal and insulator layers of the crossbar array 
wherein
{ HEAD ~ The method } 13 , wherein { TAIL ~ a number } of masking steps used for forming the crossbar array is independent of a number of metal and insulator layers of the crossbar array
HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH