TY - JOUR
T1 - Local transport properties of ferromagnetic tunnel junctions
AU - Ando, Y.
AU - Hayashi, M.
AU - Kamijo, M.
AU - Kubota, H.
AU - Miyazaki, T.
N1 - Funding Information:
This research was supported by the Sumitomo Foundation, the Storage Research Consortium, Regional Consortium Project (NEDO) and Grant-in-Aides for Scientific Research from the Ministry of Education, Science, Sports and Culture of Japan.
PY - 2001
Y1 - 2001
N2 - The local electrical properties were measured simultaneously with the topography for a SiO2/Ta(3nm)/ Fe20Ni80(3nm)/. Pt(20nm)/Fe20Ni80(3nm.)/IrMn(10nm)/Co75Fe25(4nm)/Al(0.8nm. )-oxide junction. The current image became very homogeneous and smooth after annealing at around 300°C for 1 h. Increase of tunneling magnetoresistance ratio of the junction after annealing can be well explained by taking into account both increase of the barrier height and decrease of the barrier height variation. After further annealing over 3 50 C, the barrier height decreased and leak currents were detected. Reduction of spin polarization of the ferromagnetic electrodes due to interface mixing or damage of the insulator due to the growth of grains of bottom electrode is a possible reason for the drastic decrease of TMR ratio for annealing at temperatures higher than 350°C.
AB - The local electrical properties were measured simultaneously with the topography for a SiO2/Ta(3nm)/ Fe20Ni80(3nm)/. Pt(20nm)/Fe20Ni80(3nm.)/IrMn(10nm)/Co75Fe25(4nm)/Al(0.8nm. )-oxide junction. The current image became very homogeneous and smooth after annealing at around 300°C for 1 h. Increase of tunneling magnetoresistance ratio of the junction after annealing can be well explained by taking into account both increase of the barrier height and decrease of the barrier height variation. After further annealing over 3 50 C, the barrier height decreased and leak currents were detected. Reduction of spin polarization of the ferromagnetic electrodes due to interface mixing or damage of the insulator due to the growth of grains of bottom electrode is a possible reason for the drastic decrease of TMR ratio for annealing at temperatures higher than 350°C.
KW - Atomic force microscopy
KW - Insulators
KW - Transport properties
KW - Tunneling
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U2 - 10.1016/S0304-8853(00)01106-9
DO - 10.1016/S0304-8853(00)01106-9
M3 - Article
AN - SCOPUS:33748711813
VL - 226-230
SP - 924
EP - 925
JO - Journal of Magnetism and Magnetic Materials
JF - Journal of Magnetism and Magnetic Materials
SN - 0304-8853
IS - PART I
ER -