Germanium nanowires sheathed with an oxide layer

Y. F. Zhang, Y. H. Tang, N. Wang, C. S. Lee, I. Bello, S. T. Lee
2000 Physical Review B (Condensed Matter)  
We report how the structural arrangement of germanium nanowires optimizes surface stability and enables the formation of very thin free-standing crystalline wires. Ge nanowires consisting of a crystalline Ge core and an amorphous GeO 2 sheath have been formed by laser ablation of a mixture of Ge and GeO 2 . The crystalline Ge core lies in the axial ͓211͔ direction and is terminated by the ͕111͖ facets on the surface. The GeO 2 sheath saturates the surface bonds of the core, adapts to the core
more » ... dapts to the core surface roughness, and prohibits the growth of the nanowire in the lateral direction. With such a core and sheath, the surface energy of the nanowire is reduced and the formation of very thin nanowires is thereby permitted. Phonon confinement in the Ge nanowires has been observed by Raman scattering.
doi:10.1103/physrevb.61.4518 fatcat:xjroznfytndsvescfrwumvq5hy