We review our recent work on the mechanics of silicon nanowires based on first-principles density functional theory (DFT) calculations. We focus especially on the size dependence of the Young’s modulus, but also comment on the size dependence of the residual stress and the equilibrium length of the hydrogen-passivated Si nanowires. We compare these results to prior results from classical molecu...

The electrical properties of vertically aligned silicon nanowires doped by ion implantation are studied in this paper by a combination of electron beam-induced current imaging and two terminal current-voltage measurements. By varying the implantation parameters in several process steps, uniform p- and n-doping profiles as well as p-n junctions along the nanowire axis are realized. The effective...

Germanium nanowires (GeNWs) were synthesized using chemical vapor deposition (CVD) based on vapor–liquid–solid (VLS) mechanism with Au nanoparticles as catalyst and germanium tetrachloride (GeCl4) as a precursor of germanium. Au catalysts were deposited on silicon wafer as a thin film, firstly by sputtering technique and secondly by submerging the silicon substrates in Au colloidal s...

ZnO nanostructure films were deposited by radio frequency (RF) magnetron sputtering on etched silicon (100) substrates using dry Ar/SF6 plasma, at two etching times of 5 min and 30 min, and on non etched silicon surface. Energy dispersive X-ray (EDX) technique was employed to investigate the elements contents for etched substrates as well as ZnO films, where it is found to be stoichiometric. Su...

Crystalline micrometer-long YSi2 nanowires with cross sections as small as 1 × 0.5 nm(2) can be grown on the Si(001) surface. Their extreme aspect ratios make electron conduction within these nanowires almost ideally one-dimensional, while their compatibility with the silicon platform suggests application as metallic interconnect in Si-based nanoelectronic devices. Here we combine bottom-up epi...

We report the fabrication of degenerately doped silicon (Si) nanowires of different aspect ratios using a simple, low-cost and effective technique that involves metal-assisted chemical etching (MacEtch) combined with soft lithography or thermal dewetting metal patterning. We demonstrate sub-micron diameter Si nanowire arrays with aspect ratios as high as 180:1, and present the challenges in pro...

Electric-field assisted growth and self-assembly of intrinsic silicon nanowires, in-situ, is demonstrated. The nanowires are seen to respond to the presence of a localized DC electric field set up between adjacent MEMS structures. The response is expressed in the form of improved nanowire order, alignment, and organization while transcending a gap. This process provides a simple yet reliable me...

The spds-spin-orbit-coupled tight-binding model and linearized Boltzmann transport theory is applied to calculate the electrical conductivity, the Seebeck coefficient, and the power factor of silicon nanowires (NWs) with diameters D<12nm. Using experimentally measured values for the lattice thermal conductivity we estimate the room temperature thermoelectric figure of merit to be ZT~1. Keywords...

Because of their importance in fundamental research and possible applications in nanotechnology and nanoelectronics, semiconductor nanowires have attracted much interest. In addition to the growth itself, the control of the size and location is an essential problem. Here we show the growth of ordered arrays of vertically aligned silicon nanowires by molecular beam epitaxy using prepatterned arr...

Using the non-equilibrium Green’s function techniques with interatomic potentials, we study the temperature dependence and the crossover of thermal conductance from the usual behavior proportional to the cross-sectional area at room temperature to the universal quantized behavior at low temperature for carbon nanotubes, silicon nanowires, and diamond nanowires. We find that this crossover of th...