Details

Autor(en) / Beteiligte

• Marcus, I. Carmen
• Berbezier, Isabelle
• Ronda, Antoine
• Alonso, M. Isabel
• Garriga, Miquel
• Goñi, Alejandro R
• Gomes, Elise
• Favre, Luc
• Delobbe, Anne
• Sudraud, Pierre

Titel

In-Plane Epitaxial Growth of Self-Assembled Ge Nanowires on Si Substrates Patterned by a Focused Ion Beam

Ist Teil von

• Crystal growth & design, 2011-07, Vol.11 (7), p.3190-3197

Ort / Verlag

Washington,DC: American Chemical Society

Erscheinungsjahr

2011

Quelle

Alma/SFX Local Collection

Beschreibungen/Notizen

• We report a novel method for obtaining ordered arrays of self-assembled Ge nanowires (NWs) using Au seed catalysts, with the latter deposited using a focused ion beam (FIB). For this purpose we apply a three-step process involving first FIB nanopatterning, a second step of AuSi seed formation during UHV annealing, and third the nucleation and growth of Ge NWs by combining molecular-beam epitaxy (MBE) and the vapor–liquid–solid (VLS) process. We show that FIB allows for the local implantation of Au in the areas impacted by the ion beam; the implanted Au evolves during annealing into AuSi clusters, serving as nucleation seeds for the nucleation and growth of Ge NWs. We thus prove that FIB with gold ions is a successful method to obtain gold-catalyzed self-assembled nanowires. We obtain Ge NWs of homogeneous dimensions and oriented in-plane along [110] directions, as a consequence of a strain-driven process. Wire kinking is governed by surface morphological features. Based on our experimental results, we elaborate on the general mechanisms of MBE growth of quantum wires under epitaxial strain, which we exemplify for Ge NWs on Si(001) but hold for many other lattice-mismatched semiconductor material combinations.