Growth of RuO2 nanorods in reactive sputtering

Abstract

The synthesis of RuO2 nanorods with reactive sputtering was demonstrated in this work. The synthesis process is very much like the metal organic chemical vapor deposition, except that RuO3 generated with reactive sputtering under high oxygen-to-argon flow ratio (>5SCCM∕15SCCM) (SCCM denotes cubic centimeter per minute at STP) and high substrate temperature (>300°C) is used in place of the metal organic precursor. RuO2 nanorods tend to grow steadily with constant aspect ratio (∼27) and the field-emission characteristics appear very sensitive to their spatial distribution.

Atomistic growth phenomena of reactively sputtered RuO2 and MnO2 thin films

“…When an additional Ru is added onto RuO 2 (110) with already adsorbed Ru and dissociated O 2 molecule, it is desorbed. This excess of oxygen is consistent with hyperoxide formation, 12,14,15 which is relevant for nucleation of RuO 2 nanorods.…”

“…This is consistent with previous work. 12,14 Based on the comparison with literature on RuO 2 nanorods, 12,14-16 it may be speculated that RuO 2 nanorods shown in Fig. 2 deviations is to be expected for polycrystalline aggregates where one morphological feature contains several coherency domains.…”

“…Composites or layered RuO 2 -MnO 2 are relevant for supercapacitor applications. 11 RuO 2 nanorods can be formed via reactive sputtering, and Lin et al 12 suggested that Ru hyperoxides, such as RuO 3 and RuO 4 , are precursors for RuO 2 nanorod formation as these are volatile. Cross et al 13 reported that the growth of RuO 2 nanorods is mediated through the thermal diffusion of Ru hyperoxide precursors across the nanorod surface.…”

RuO2 Nanowires and RuO2/TiO2 Core/Shell Nanowires: From Synthesis to Mechanical, Optical, Electrical, and Photoconductive Properties

“…[3b,4] Recently, RuO 2 NWs have been synthesized using pure Ru as metal target under different flux ratios of O 2 /Ar in a reactive sputtering system. [5] For core/shell structures, extensive research has been carried out on systems such as Ge/Si, [6] GaN/AlN/AlGaN, [7] Ta 2 O 5 /SiO 2 , [8] and Fe 3 O 4 /MgO. [9] The Ge/Si core/shell NW, for example, is a high-performance field-effect transistor because of the reduced carrier scattering.…”

Influence of Electrostatic Forces on the Growth of One‐Dimensional Nanostructures

“…The growth of nanomaterial structures in general has attracted a great deal of interest and excitement over the past decade and a half with recent attention to the growth of onedimensional nanorods [1][2][3][4]. Special interest has been given to RuO 2 nanostructures because of their attractive chemical and physical properties [5]. Ruthenium dioxide is a rutiletype tetragonal oxide that exhibits low electrical resistivity (∼40 μΩ-cm) and high catalytic activity [6].…”