A time-resolved numerical study of the vapor-liquid-solid growth kinetics describing the initial nucleation phase as well as pulsed deposition processes.

Today, the vapor-liquid-solid (VLS) growth mechanism is a common process for the metal catalyzed bottom-up growth of semiconductor nanowires (NWs). Nevertheless, most of the literature only is concerned with the steady-state NW growth which applies when the amount of material supplied is equal to the amount consumed by the NW growth at the same time. While this description is suitable for chemical vapor deposition (CVD) or electron beam evaporation (EBE) processes after the initial nucleation time, problems arise when pulsed growth processes like pulsed laser deposition (PLD) are used since in this case the steady state growth condition cannot be applied.

Increasing the efficiency of polymer solar cells by silicon nanowires.

Silicon nanowires have been introduced into P3HT:[60]PCBM solar cells, resulting in hybrid organic/inorganic solar cells. A cell efficiency of 4.2% has been achieved, which is a relative improvement of 10% compared to a reference cell produced without nanowires.

Growth of axial SiGe heterostructures in nanowires using pulsed laser deposition.

Axial heterojunctions between pure silicon and pure germanium in nanowires have been realized combining pulsed laser deposition, chemical vapor deposition and electron beam evaporation in a vapor-liquid-solid nanowire growth experiment using gold nanoparticles as catalyst for the 1D wire growth. Energy dispersive x-ray mappings and line scans show a compositional transition from pure silicon to pure germanium and vice versa with exponential and thus comparably sharp transition slopes. Based on these results not only Si-Ge heterojunctions seem to be possible using the vapor-liquid-solid growth process but also heterojunctions in optoelectronic III-V compounds such as InGaAs/GaAs or group III nitride compounds such as InGaN/GaN as well as axial p-n junctions in Si nanowires.

Growth of doped silicon nanowires by pulsed laser deposition and their analysis by electron beam induced current imaging.

Doped silicon nanowires (NWs) were epitaxially grown on silicon substrates by pulsed laser deposition following a vapour-liquid-solid process, in which dopants together with silicon atoms were introduced into the gas phase by laser ablation of lightly and highly doped silicon target material. p-n or p(++)-p junctions located at the NW-silicon substrate interfaces were thus realized. To detect these junctions and visualize them the electron beam induced current technique and two-point probe current-voltage measurements were used, based on nanoprobing individual silicon NWs in a scanning electron microscope.