title: Fabrication of high performance field-effect transistors and practical Schottky contacts using hydrothermal ZnO nanowires.
abstract: The production of large quantities of single crystalline semiconducting ZnO nanowires (NWs) at low cost can offer practical solutions to realizing several novel electronic/optoelectronic and sensor applications on an industrial scale. The present work demonstrates high-density single crystalline NWs synthesized by a multiple cycle hydrothermal process at ∼100 °C. The high carrier concentration in such ZnO NWs is greatly suppressed by a simple low cost thermal annealing step in ambient air at ∼450 °C. Single ZnO NW FETs incorporating these modified NWs are characterized, revealing strong metal work function-dependent charge transport, unobtainable with as-grown hydrothermal ZnO NWs. Single ZnO NW FETs with Al as source and drain (s/d) contacts show excellent performance metrics, including low off-state currents (fA range), high on/off ratio (10(5)-10(7)), steep subthreshold slope (<600 mV/dec) and excellent field-effect carrier mobility (5-11 cm(2)/V-s). Modified ZnO NWs with platinum s/d contacts demonstrate excellent Schottky transport characteristics, markedly different from a reference ZnO NW device with Al contacts. This included abrupt reverse bias current-voltage saturation characteristics and positive temperature coefficient (∼0.18 eV to 0.13 eV). This work is envisaged to benefit many areas of hydrothermal ZnO NW research, such as NW FETs, piezoelectric energy recovery, piezotronics and Schottky diodes.
authors.affiliation: Université François Rabelais de Tours, CNRS, GREMAN UMR 7347, 16 rue Pierre et Marie Curie, 37071 TOURS Cedex2, France.
authors.forename: Charles
authors.initials: C
authors.lastname: Opoku
authors.forename: Abhishek Singh
authors.initials: AS
authors.lastname: Dahiya
authors.forename: Christopher
authors.initials: C
authors.lastname: Oshman
authors.forename: Christophe
authors.initials: C
authors.lastname: Daumont
authors.forename: Frederic
authors.initials: F
authors.lastname: Cayrel
authors.forename: Guylaine
authors.initials: G
authors.lastname: Poulin-Vittrant
authors.forename: Daniel
authors.initials: D
authors.lastname: Alquier
authors.forename: Nicolas
authors.initials: N
authors.lastname: Camara