[16p-P6-1~22] 12.1 Fabrications and Structure Controls

[16p-P6-21] Fabrication of Ni₇₈Fe₂₂/Alq₃/Ni₇₈Fe₂₂ nanoscale junctions utilizing thin-film edges and their structural and electrical properties

Takahiro Misawa¹, Sumito Mori¹, Takashi Komine², Norihisa Hoshino³, Tomoyuki Akutagawa³, Masaya Fujioka¹, 〇Hideo Kaiju¹, Junji Nishii¹ (1.RIES Hokkaido Univ., 2.Eng. Ibaraki Univ., 3.IMRAM Tohoku Univ.)

Keywords:molecule, nanoscale junction, thin film

We have fabricated Ni₇₈Fe₂₂/tris (8-hydroxy-quinoline) aluminum (Alq₃)/Ni₇₈Fe₂₂ nanoscale junctions utilizing thin-film edges and investigated their structural and electrical properties. This nanoscale junction consists of Alq₃ molecules sandwiched between two of Ni₇₈Fe₂₂ thin films whose edges are crossed. In this structure, the junction area is determined by the film thickness, i. e., 1−20-nm-thick films could produce 1×1–20×20-nm² nanoscale junctions. Using the established fabrication technique, we have successfully demonstrated the formation of Ni₇₈Fe₂₂/Alq₃/Ni₇₈Fe₂₂ junctions with a junction area of 16×17 nm² without using conventional lithography such as electron-beam or optical lithography. The current-voltage (I-V) characteristics of this nanoscale junction show the ohmic behavior, which suggests the observation of the multiple quantized conductances in the ballistic regime. The I-V characteristics for various junction areas, ranging from micro to nanometers, are also discussed. The nanoscale-junction fabrication technique utilizing thin-film edges will open up new opportunities for not only the creation of next-generation nanodevices but also the discovery of new physical and/or chemical phenomena in nanoscale systems.