Low thermal-budget fabrication of sputtered-PZT capacitor on multilevel interconnects for embedded FeRAM

Low temperature fabrication of the PZT capacitor is achieved by O/sub 2/-free sputtering on the oxygen-doped iridium (IrO). Oxygen gas stabilizes the non-ferroelectric pyrochlore phase, therefore O/sub 2/-free PZT sputtering enforces the deposition of ferroelectric perovskite phase. The Ir(O) bottom electrode, in which the oxygen atoms are fixed in the Ir-lattice, also helps the direct deposition of the perovskite PZT even at 450/spl deg/C-475/spl deg/C. This low thermal-budget process enables us to fabricate the PZT capacitor on the multilevel Al-interconnects for the FeRAM-embedded logic LSI.