title: Nanocontact Disorder in Nanoelectronics for Modulation of Light and Gas Sensitivities.
abstract: To fabricate reliable nanoelectronics, whether by top-down or bottom-up processes, it is necessary to study the electrical properties of nanocontacts. The effect of nanocontact disorder on device properties has been discussed but not quantitatively studied. Here, by carefully analyzing the temperature dependence of device electrical characteristics and by inspecting them with a microscope, we investigated the Schottky contact and Mott's variable-range-hopping resistances connected in parallel in the nanocontact. To interpret these parallel resistances, we proposed a model of Ti/TiOx in the interface between the metal electrodes and nanowires. The hopping resistance as well as the nanocontact disorder dominated the total device resistance for high-resistance devices, especially at low temperatures. Furthermore, we introduced nanocontact disorder to modulate the light and gas responsivities of the device; unexpectedly, it multiplied the sensitivities compared with the intrinsic sensitivity of the nanowires. Our results improve the collective understanding of electrical contacts to low-dimensional semiconductor devices and will aid performance optimization in future nanoelectronics.
authors.affiliation: Department of Physics, National Chung Hsing University, Taichung, 40227, Taiwan.
authors.forename: Yen-Fu
authors.initials: YF
authors.lastname: Lin
authors.affiliation: Department of Electrophysics, National Chiao Tung University, Hsinchu 30010, Taiwan.
authors.forename: Chia-Hung
authors.initials: CH
authors.lastname: Chang
authors.affiliation: Department of Electrophysics, National Chiao Tung University, Hsinchu 30010, Taiwan.
authors.forename: Tsu-Chang
authors.initials: TC
authors.lastname: Hung
authors.affiliation: Department of Electrophysics, National Chiao Tung University, Hsinchu 30010, Taiwan.
authors.forename: Wen-Bin
authors.initials: WB
authors.lastname: Jian
authors.affiliation: WPI Center for Materials Nanoarchitechtonics (WPI-MANA), National Institute for Materials Science (NIMS), Tsukuba, Ibaraki 305-0044, Japan.
authors.forename: Kazuhito
authors.initials: K
authors.lastname: Tsukagoshi
authors.affiliation: Department of Materials Science, National Chiao Tung University, Hsinchu 30010, Taiwan.
authors.forename: Yue-Han
authors.initials: YH
authors.lastname: Wu
authors.affiliation: Department of Materials Science, National Chiao Tung University, Hsinchu 30010, Taiwan.
authors.forename: Li
authors.initials: L
authors.lastname: Chang
authors.affiliation: Department of Chemistry, State University of New York at Binghamton, Binghamton, New York 13902-6000, USA.
authors.forename: Zhaoping
authors.initials: Z
authors.lastname: Liu
authors.affiliation: Department of Chemistry, State University of New York at Binghamton, Binghamton, New York 13902-6000, USA.
authors.forename: Jiye
authors.initials: J
authors.lastname: Fang