You are here : Home > The Sinaps team > Confined silicon nanowire growh for low cost photovoltaics

Ludovic Dupré

Confined silicon nanowire growh for low cost photovoltaics

Published on 24 October 2013

Thesis presented October 24, 2013

Silicon nanowires are promising objects but their integration in electronic devices such as photvoltaic solar cells relies on the ability to control their production and tailor their structural properties. In this thesis we present a method to produce nanowire matrices using a gold or copper catalysed growth process by chemical vapor deposition and using a nanoporous alumina growth template. This method enables the fabrication of ultra-dense nanowire arrays (1.10^{10} nanowires/cm²) on non preferential substrate or heterostructures such as germanium nanowires on silicon substrate. Using X-ray diffraction we also show that the structural quality of the template grown nanowires is very good in spite of their non preferential substrate and the presence of a small cristalline lattice strain. The control of germanium nanowires strain is also demonstrated by embeding them in a silicon nitride shell. Besides, new results are presented concerning the catalyst contamination of silicon nanowires. Silicon nanowires integration in photovoltaic devices is eventually demonstrated using a radial geometry for the PN junction between the core and the shell of the nanowires.

X-Ray diffraction, Photovoltaics, Nanoporous Alumina, Nanowires, Silicon, Chemical Vapor Deposition

On-line thesis.