Two-level BEOL processing for rapid iteration in MRAM development. - Michael C. Gaidis; Eugene J. O'Sullivan; Janusz Jozef Nowak; Yu Lu; Sivananda K. Kanakasabapathy; Philip Louis Trouilloud; Daniel Christopher Worledge; Solomon Assefa; Keith R. Milkove; George P. Wright; William J. Gallagher (IBM J. Res. Dev., 2006)