title: Vertically Aligned Ge Nanowires on Flexible Plastic Films Synthesized by (111)-Oriented Ge Seeded Vapor-Liquid-Solid Growth.
abstract: Transfer-free fabrication of vertical Ge nanowires (NWs) on a plastic substrate is demonstrated using a vapor-liquid-solid (VLS) method. The crystal quality of Ge seed layers (50 nm thickness) prepared on plastic substrates strongly influenced the VLS growth morphology, i.e., the density, uniformity, and crystal quality of Ge NWs. The metal-induced layer exchange yielded a (111)-oriented Ge seed layer at 325 °C, which allowed for the VLS growth of vertically aligned Ge NWs. The Ge NW array had almost the same quality as that formed on a bulk Ge(111) substrate. Transmission electron microscopy demonstrated that the Ge NWs were defect-free single crystals. The present investigation paves the way for advanced electronic optical devices integrated on a low-cost flexible substrate.
authors.affiliation: †Institute of Applied Physics, University of Tsukuba, Tsukuba, Ibaraki 305-8573, Japan.
authors.forename: Kaoru
authors.initials: K
authors.lastname: Toko
authors.affiliation: †Institute of Applied Physics, University of Tsukuba, Tsukuba, Ibaraki 305-8573, Japan.
authors.forename: Mitsuki
authors.initials: M
authors.lastname: Nakata
authors.affiliation: ‡International Center for Materials Nanoarchitectonics, National Institute for Materials Science, Namiki, Tsukuba, Ibaraki 305-0044, Japan.
authors.forename: Wipakorn
authors.initials: W
authors.lastname: Jevasuwan
authors.affiliation: ‡International Center for Materials Nanoarchitectonics, National Institute for Materials Science, Namiki, Tsukuba, Ibaraki 305-0044, Japan.
authors.forename: Naoki
authors.initials: N
authors.lastname: Fukata
authors.affiliation: †Institute of Applied Physics, University of Tsukuba, Tsukuba, Ibaraki 305-8573, Japan.
authors.forename: Takashi
authors.initials: T
authors.lastname: Suemasu
keywords: chemical vapor deposition; crystal orientation control; flexible substrates; germanium nanowires; metal-induced crystallization