Electrical Nanocontact Between Bismuth Nanowire Edges and Electrodes

• Published in: Journal of electronic materials 2010-09, Vol.39 (9), p.1536-1542
• Main Authors: Murata, Masayuki, Nakamura, Daiki, Hasegawa, Yasuhiro, Komine, Takashi, Uematsu, Daisuke, Nakamura, Shinichiro, Taguchi, Takashi
• Format: Article
• Language: English
• Subjects: Characterization and Evaluation of Materials; Chemical elements; Chemistry and Materials Science; Condensed matter: electronic structure, electrical, magnetic, and optical properties; Cross-disciplinary physics: materials science; rheology; Electrodes; Electronic structure and electrical properties of surfaces, interfaces, thin films and low-dimensional structures; Electronic transport phenomena in thin films and low-dimensional structures; Electronics and Microelectronics; Exact sciences and technology; Heat resistance; Instrumentation; Ion and electron beam-assisted deposition; ion plating; Materials Science; Methods of deposition of films and coatings; film growth and epitaxy; Nanoscale materials and structures: fabrication and characterization; Nanowires; Optical and Electronic Materials; Physics; Quantum wires; Solid State Physics; Thermoelectric effects
• ISSN: 0361-5235; 1543-186X
• DOI: 10.1007/s11664-010-1282-5

Three methods for attaching electrodes to a bismuth nanowire sample were investigated. In the first and second methods, thin layers of titanium and copper were deposited by ion plating under vacuum onto the edge surface of individual bismuth nanowire samples that were encapsulated in a quartz template. Good electrical contact between the electrodes and the nanowire was achieved using silver epoxy and conventional solder on the thin-film layers in the first and second methods, respectively. In the third method, a low-melting-point solder was utilized and was also successful in achieving good electrical contact in air atmosphere. The connection methods showed no difference in terms of resistivity temperature dependence or Seebeck coefficient. The third method has an advantage in that nanocontact is easily achieved; however, diffusion of the solder into the nanowire allows contamination near the melting point of the solder. In the first and second methods, the thin-film layer enabled electrical contact to be more safely achieved than the direct contact used in the third method, because the thin-film layer prevented diffusion of binder components.