TY - JOUR
T1 - Influence of thermal annealing on oxidation states of Al-oxide in spin tunneling junctions
AU - Kaiju, Hideo
AU - Otaka, Yuki
AU - Shiiki, Kazuo
N1 - Funding Information:
This research was supported by a grant from the Japan Society for the Promotion of Science (JSPS). The authors would like to express gratitude to Mr. Harada for his useful discussions and valuable suggestions with respect to dielectric properties.
PY - 2006/8
Y1 - 2006/8
N2 - The dielectric constant in annealing coercive differential spin tunneling junctions Co/Al-oxide/Co has been investigated in order to clear the influence of thermal annealing on oxidation states. Al oxidized naturally in pure O2 shows the relative dielectric constant of 10-40 before annealing. It indicates that Al oxidized in pure O2 can be AlO2 because the dielectric constant of AlO2 is approximately 22.7. This dielectric measurement result is in good agreement with XPS analysis results that O/Al ratio is 1.9-2.0. After annealing at temperature ranging from room temperature up to 250 °C, the relative dielectric constant approaches approximately 8.0, which is equal to that of Al2O3. This indicates that the phase of Al-oxide is changing from AlO2 to Al2O3 by annealing. This dielectric measurement will help investigate the oxidation state, such as chemical composition for junctions themselves.
AB - The dielectric constant in annealing coercive differential spin tunneling junctions Co/Al-oxide/Co has been investigated in order to clear the influence of thermal annealing on oxidation states. Al oxidized naturally in pure O2 shows the relative dielectric constant of 10-40 before annealing. It indicates that Al oxidized in pure O2 can be AlO2 because the dielectric constant of AlO2 is approximately 22.7. This dielectric measurement result is in good agreement with XPS analysis results that O/Al ratio is 1.9-2.0. After annealing at temperature ranging from room temperature up to 250 °C, the relative dielectric constant approaches approximately 8.0, which is equal to that of Al2O3. This indicates that the phase of Al-oxide is changing from AlO2 to Al2O3 by annealing. This dielectric measurement will help investigate the oxidation state, such as chemical composition for junctions themselves.
KW - Al-oxide
KW - Annealing
KW - Dielectric constant
KW - Ion-beam sputtering
KW - Spin tunneling junctions
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U2 - 10.1016/j.jmmm.2005.11.017
DO - 10.1016/j.jmmm.2005.11.017
M3 - Article
AN - SCOPUS:33645987296
SN - 0304-8853
VL - 303
SP - 256
EP - 260
JO - Journal of Magnetism and Magnetic Materials
JF - Journal of Magnetism and Magnetic Materials
IS - 1
ER -