Summary
In this work we report on the formation, of copper-germanide/germanium nanowire (NW) heterostructures with atomically sharp interfaces. The copper-germanide (Cu3Ge) formation process is enabled by a chemical reaction between metallic Cu pads and vapor-liquid-solid (VLS) grown Ge-NWs. The atomic scale aligned formation of the Cu3Ge segments is controlled by in situ SEM monitoring at 310 °C thereby enabling length control of the intrinsic Ge-NW down to a few nm. The single crystal Cu3Ge/Ge/Cu3Ge heterostructures were used to fabricate Ω-gated Ge-NW field effect transistors with Schottky Cu3Ge source/drain contacts. Temperature dependent I/V measurements revealed the metallic properties of the Cu3Ge contacts with a maximum current carrier density of 5 × 107 A/cm2. Prior to the gate deposition the intrinsic Ge-NW was modified with a focussed Ga+ ion beam. According to the thermoionic emission theory we determined an effective Schottky barrier height reduction from 218 meV to about 115 meV due to Ga+ implantation.
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References
Barrelet, C. J., Agarwal, R., Lieber, C. M. (2005): Lasing in single cadmium sulfide nanowire optical cavities. Nano Letters, 5: 917
CaRIne Crystallography 3: 1
Chao, Y.-L., Xu, Y., Scholz, R., Woo, J. C. S. (2006): Characterization of copper germanide as contact metal for advanced MOSFETs. IEEE Electron Device Letters, 27: 7
Cui, Y., Duan, X., Hu, J., Lieber, C. M. J. (2000): Doping and electrical transport in silicon nanowires. Physical Chemistry B, 104: 5213
Cui, Y., Lieber, C. M. (2001): Functional nanoscale electronic devices assembled using silicon nanowire Building Blocks. Science, 291: 891
Duan, X., Huang, Y., Cui, Y., Wang, J., Lieber, C. M. (2000): Indium phosphide nanowires as building blocks for nanoscale electronic and optoelectronic devices. Nature, 409: 66
Duan, X., Huang, Y., Lieber, C. M. (2002): Nonvolatile Memory and Programmable Logic from Molecule-Gated Nanowires. Nano Letters, 2: 487
Gaudet, S., Detavernier, C., Kellock, A. J., Desjardins, P., Lavoie, C. J. (2006): Thin film reaction of transition metals with germanium. Vac Sci Technol A, 24: 474
Gradecak, S., Qian, F., Li, Y., Park, H., Lieber, C. M. (2005): GaN nanowire lasers with low lasing thresholds. Appllied Physics Letters, 87: 173111
Huang, Y.; Duan, X., Cui, J., Lauhon, J., Kim, K.-H., Lieber, C. M. (2001): Logic gates and computation from assembled nanowire building blocks. Science, 294: 1313
Krusin-Elbaum, L., Aboelfotoh, M. O. (1991): Unusually low resistivity of copper germanide thin films formed at low temperatures. Applied Physics Letters, 58: 1341
Lin, Y., Lu, W., Wu, W., Bai, J., Chen, L. J., Tu, K. N., Huang, Y. (2008): Single crystalline PtSi nanowires, PtSi/Si/PtSi nanowire heterostructures, and nanodevices. Nano Letters, 8: 913
Lu, W., Xiang, J., Timko, B. P., Wu, Y., Lieber, C. M. (2005): One-dimensional hole gas in germanium/silicon nanowire heterostructures. Proceedings of the National Acadamy of Science of the United States of America, 102: 10046
Maeda, Y., Tsukamoto, N., Yazawa, Y., Kanemitsu, Y., Matsumoto, Y. (1991): Visible photoluminescence of germanium microcrystals embedded in silica glassy matrixes. Applied Physics Letters, 59: 3168
Moore, G. E. (1965): Cramming more components onto integrated circuits. Electronics, 38: 8
Nam, C. Y., Tham, D., Fischer, J. E. (2005): Disorder effects in focused-ion-beam-deposited Pt contacts on GaN nanowires. Nano Letters, 5: 2029
Persson, A. I., Pettersson, H., Trägardh, J., Samuelson, L. (2006): Infrared photodetectors in heterostructure nanowires. Nano Letters, 6: 229
Prince, M. B. (1953): Drift mobilities in semiconductors. I. Germanium. Bell Telephone Laboratories, 92
Song, Y., Schmitt, A. L., Jin, S. (2007): Ultralong single-crystal metallic Ni2Si nanowires with low resistivity. Nano Letters, 7: 965
Sze, S. M. (1981): Physics of Semiconductor Devices. New York: Wiley
Tawancy, H. M., Aboelfotoh, M. O. J. (1995): Effect of phase transitions in copper-germanium thin film alloys on their electrical resistivity. Materials Science, 30: 6053
Weber, W. M., Geelhaar, L., Graham, A. P., Unger, E., Duesberg, G. S., Liebau, M., Pamler, W., Che'ze, C., Riechert, H., Lugli, P., Kreupl, F. (2006): Silicon-nanowire transistors with intruded nickel-silicide contacts. Nano Letters, 6: 2660
Wu, Y., Xiang, J., Yang, C., Lu, W., Lieber, C. M. (2004): Single-crystal metallic nanowires and metal/semiconductor nanowire heterostructures. Nature, 430: 61
Xiang, J., Lu, W., Hu, Y., Wu, Y., Yan, H., Lieber, C. M. (2006): Ge/Si nanowire heterostructures as high-performance field-effect transistors. Nature, 441: 489
Yamamoto, K., Kohno, H., Takeda, S., Ichikawa, S. (2006): Fabrication of iron silicide nanowires from nanowire templates. Applied Physics Letters, 89: 083107
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Burchhart, T., Lugstein, A., Zeiner, C. et al. Nanowire-metal heterostructures for high performance MOSFETs. Elektrotech. Inftech. 127, 171–175 (2010). https://doi.org/10.1007/s00502-010-0739-9
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DOI: https://doi.org/10.1007/s00502-010-0739-9