Heteroepitaxial growth of Ge nanowires was carried out on Si(111) substrates by MBE. Au seeds were used as precursor for the VLS growth of the nanowires. Even if the Au droplets do not act as catalyst for the dissociation of gas, they are local preferential areas where the energetic barrier of Ge nucleation is lowered compare to the remaining non activated surface. Two sets of Au seeds were use...

A tunable structural engineering of nanowires based on template-assisted alloying and phase segregation processes is demonstrated. The Au-Ge system, which has a low eutectic temperature and negligible solid solubility (<10(-3) atom %) of Au in Ge at low temperatures, is utilized. Depending on the Au concentration of the initial nanowires, final structures ranging from nearly periodic nanodisk p...

High-purity germanium compounds (e.g. germanium dioxide) are used these days in several applications (e.g. germanium-based detectors, semiconductors, fiber-optic systems). Thus, reliable methods for the routine determination of trace element impurities from germanium compounds must be developed. In this study, inductively coupled plasma mass spectrometry, inductively coupled plasma optical emis...

In this Letter we report on the exploration of axial metal/semiconductor (Al/Ge) nanowire heterostructures with abrupt interfaces. The formation process is enabled by a thermal induced exchange reaction between the vapor-liquid-solid grown Ge nanowire and Al contact pads due to the substantially different diffusion behavior of Ge in Al and vice versa. Temperature-dependent I-V measurements reve...

We study I-V characteristics and time dependence of ∆VT under different VGS, temperature stresses and recovery in undoped back-gated Ge nanowire. We show that charge trapping is dominant mechanism of VGS, temperature stress and recovery by fitting measured ∆VT with stretched-exponential equation.

We synthesized thermally stable graphene-covered Ge (Ge@G) nanowires and applied them in field emission devices. Vertically aligned Ge@G nanowires were prepared by sequential growth of the Ge nanowires and graphene shells in a single chamber. As a result of the thermal treatment experiments, Ge@G nanowires were much more stable than pure Ge nanowires, maintaining their shape at high temperature...

Hybrid field-effect-transistors (FETs) with germanium nanowire (NW) arrays and organic gate dielectric are presented. The nanowire deposition steps are fully compatible with printed electronics route. NW FETs demonstrate good performance with On/Off ratios of ~10 and hole mobilities of ~13 cm/Vs in both nitrogen and air atmosphere. These results suggest that the hybrid nanowire FETs could be us...

Microand nanostructured surfaces found in biological systems have inspired the fabrication of functional materials with unique optical, chemical, and mechanical properties. Inspired by the nanofibrillar structures of gecko adhesives, we recently reported self-selective, chemical connectors (i.e., fasteners) based on interpenetrating nanowire (NW) forests, which primarily use the highly tunable ...

The effects of partial substitution of Ge for Si in cobalt germanosilicide (CoSi(1-x)Ge(x) and Co(2)Si(1-x)Ge(x)) nanowires (NWs) on the electrical transport, magnetic properties, and magnetoresistance (MR) have been investigated. Cobalt germanosilicide NWs were synthesized by a spontaneous chemical vapor transport growth method. The Ge concentration can be selectively controlled from 0 to 15% ...

Local strain and Ge content distribution in self-assembled, in-plane Ge/Si nanowires grown by combining molecular beam epitaxy and the metal-catalyst assisted-growth method were investigated by tip-enhanced Raman scattering. We show that this technique is essential to study variations of physical properties of single wires at the nanoscale, a task which cannot be achieved with conventional micr...