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TRANSCRIPT
H. Nakanishi, H. Omae, Y. Fujiwara, M. Jimbo*, T. Kobayashi, S. ShiomiDepartment of Physics Engineering, Mie Univ., Kurima-machiya-machi 1577, Tsu 514-8507, Japan
* Daido Institute of Technology, Takiharu 10-3, Minami-ku, Nagoya 457-8530, Japan
Magnetic tunnel transistors (MTTs) with double tunnel junctions were prepared in order to investigate the emittervoltage dependence of a magneto-current (MC). A three-terminal structure was fabricated, using metal shadow masks. It wasobserved that hot electrons contributed to a collector current. A transfer ratio of over 10-3 was obtained in an MTT with doubletunnel junctions. The MC decreased gradually with increasing emitter voltage. The emitter voltage at which the MC decreased tohalf its original value was over 1.5 V.
Key words: magnetic tunnel transistor, hot electron, tunnel junction, spin valve, transfer ratio
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Fig. 1 Illustrations of (a) sample structures and (b)
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Fig. 2 Arrangement of the metal masks.
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J. Magn. Soc. Jpn., 30, 188-191 (2006) (Paper)
188 Journal of the Magnetics Society of Japan Vol. 30, No., 2, 2006
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Journal of the Magnetics Society of Japan Vol. 30, No., 2, 2006 189
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Fig. 6 Current�voltage characteristics of a collector
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Fig. 7 Hot electron contribution to the collector current.
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Fig. 9 Emitter�base voltage dependence of transfer ratios.
190 Journal of the Magnetics Society of Japan Vol. 30, No., 2, 2006190
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Journal of the Magnetics Society of Japan Vol. 30, No., 2, 2006 191