| 摘要 |
Provided is a planarization method whereby a metal film formed before the formation of an MTJ element of an MRAM can be reliably planarized. An MTJ element (48) is formed as follows: after a copper film (43) embedded in a SiO2 film (42) is formed on a wafer (W), the surface of said copper film (43) is exposed to an oxygen GCIB so as to planarize said copper film (43); after a tantalum film (44) is formed or after a ruthenium film (45) or another tantalum film (46) is formed, said tantalum film (44), ruthenium film (45), or other tantalum film (46) is exposed to an oxygen GCIB so as to planarize said tantalum film (44), ruthenium film (45), or other tantalum film (46); after a PtMn film (47) is formed, the surface thereof is exposed to an oxygen GCIB so as to planarize said PtMn film (47); a CoFe thin film (55) and a ruthenium thin film (56) are then formed; and a CoFeB thin film (51), a MgO thin film (50), and another CoFeB thin film (52) are formed in that order. |
