Title :
Low switching field of sub-micron sized MTJs with synthetic ferrimagnet free layer based on NiFe/Ru/NiFe multilayers
Author :
Lee, Young Min ; Kubota, Hitoshi ; Ando, Yasuo ; Miyazaki, Terunobu
Author_Institution :
Dept. of Appl. Phys., Tohoku Univ., Sendai, Japan
Abstract :
A synthetic ferrimagnetic multilayer was proposed for the free layer of MTJ. Synthetic ferrimagnet has a single domain structure even at low aspect ratio, thus, the switching field of MTJ can be remained low for the very small sized cell. MTJs with synthetic ferrimagnetic free layer based on NiFe were fabricated to reduce switching field. Stacking structure of Si/SiO2(10000)/Ta(200)/NiFe(t1)/CoFe(0∼3)/Ru(4)/CoFe(0∼3)/NiFe(t2)/Al (20)-O/CoFe(40)/IrMn(100)/Cr(50)/Au(500) were deposited by high vacuum magnetron sputtering. MR curves were measured by using a conductive atomic force microscope. From the MR curves, switching field was defined the width of hysteresis swept 90% of normalized MR as two times of switching field.
Keywords :
aluminium compounds; atomic force microscopy; chromium; cobalt alloys; ferrimagnetic materials; gold; iridium alloys; iron alloys; magnetic hysteresis; magnetic multilayers; magnetic switching; magnetic tunnelling; manganese alloys; nickel alloys; ruthenium; silicon; silicon compounds; sputter deposition; tantalum; MR curves; Si-SiO2-Ta-NiFe-CoFe-Ru-CoFe-NiFe-AlO-CoFe-IrMn-Cr-Au; conductive atomic force microscope; domain structure; high vacuum magnetron sputtering; hysteresis; stacking structure; submicron sized MTJ; switching field; synthetic ferrimagnet free layer; Atomic force microscopy; Atomic layer deposition; Atomic measurements; Conductivity measurement; Ferrimagnetic materials; Force measurement; Magnetic field measurement; Nonhomogeneous media; Sputtering; Stacking;
Conference_Titel :
Magnetics Conference, 2005. INTERMAG Asia 2005. Digests of the IEEE International
Print_ISBN :
0-7803-9009-1
DOI :
10.1109/INTMAG.2005.1464428
