Crystallization of amorphous SiO2 microtubes catalyzed by lithium

Amorphous silica formed by thermally oxidizing silicon is commonly eligible for lithographic patterning or can be grown on patterned substrates. However, it is still a challenge to combine controlled microstructuring with controlled crystallization of SiO2. Here, it is shown that traces of volatile lithium species transported through the gas phase catalyze the crystallization of silica integrated into common silicon microstructures. The selected crystallization temperature determines which polymorph forms. As an example, the formation of quartz, tridymite, and cristobalite microtubes by thermally oxidizing macroporous silicon is investigated. Lithium-induced crystallization may extend state-of-the-art silicon technology and yield nano- and microstructures consisting of different silica polymorphs, which are, in contrast to many functional oxides, nontoxic. © 2007 WILEY-VCH Verlag GmbH & Co. KGaA.

Full Text

Duke Authors

Cited Authors

  • Zhao, L; Li, N; Langner, A; Steinhart, M; Tan, TY; Pippel, E; Hofmeister, H; Tu, KN; Gösele, U

Published Date

  • 2007

Published In

Volume / Issue

  • 17 / 12

Start / End Page

  • 1952 - 1957

International Standard Serial Number (ISSN)

  • 1616-301X

Digital Object Identifier (DOI)

  • 10.1002/adfm.200601104

Citation Source

  • SciVal