title: Fabrication of single-crystal silicon nanotubes with sub-10 nm walls using cryogenic inductively coupled plasma reactive ion etching.
abstract: Single-crystal silicon nanostructures have attracted much attention in recent years due in part to their unique optical properties. In this work, we demonstrate direct fabrication of single-crystal silicon nanotubes with sub-10 nm walls which show low reflectivity. The fabrication was based on a cryogenic inductively coupled plasma reactive ion etching process using high-resolution hydrogen silsesquioxane nanostructures as the hard mask. Two main etching parameters including substrate low-frequency power and SF6/O2 flow rate ratio were investigated to determine the etching mechanism in the process. With optimized etching parameters, high-aspect-ratio silicon nanotubes with smooth and vertical sub-10 nm walls were fabricated. Compared to commonly-used antireflection silicon nanopillars with the same feature size, the densely packed silicon nanotubes possessed a lower reflectivity, implying possible potential applications of silicon nanotubes in photovoltaics.
authors.affiliation: School of Physics and Electronics, Key Laboratory for Micro-Nano Optoelectronic Devices of Ministry of Education, State Key Laboratory for Chemo/Biosensing and Chemometrics, Hunan University, Changsha 410082, People's Republic of China. CAS Center for excellence in Nanoscience, National Center for Nanoscience and Technology, Beijing 100190, People's Republic of China.
authors.forename: Zhiqin
authors.initials: Z
authors.lastname: Li
authors.forename: Yiqin
authors.initials: Y
authors.lastname: Chen
authors.forename: Xupeng
authors.initials: X
authors.lastname: Zhu
authors.forename: Mengjie
authors.initials: M
authors.lastname: Zheng
authors.forename: Fengliang
authors.initials: F
authors.lastname: Dong
authors.forename: Peipei
authors.initials: P
authors.lastname: Chen
authors.forename: Lihua
authors.initials: L
authors.lastname: Xu
authors.forename: Weiguo
authors.initials: W
authors.lastname: Chu
authors.forename: Huigao
authors.initials: H
authors.lastname: Duan