A method for forming an MTJ structure suitable for use in a MRAM device having a bottom electrode including a layer of platinum, ruthenium, iridium, rhodium, osmium, palladium or their oxides and having reduced surface roughness to improve the hysteresis loop characteristics of the resulting MTJ structure. The bottom electrode layer may also combine the functions of both the seeding layer and bottom electrode of the conventional two-layer structure, thereby simplifying the manufacturing process.