title: Soft-chemistry-based routes to epitaxial α-quartz thin films with tunable textures.
abstract: Piezoelectric nanostructured quartz films of high resonance frequencies are needed for microelectronic devices; however, synthesis methods have been frustrated by the inhomogeneous crystal growth, crystal twinning, and loss of nanofeatures upon crystallization. We report the epitaxial growth of nanostructured polycrystalline quartz films on silicon [Si(100)] substrates via the solution deposition and gelation of amorphous silica thin films, followed by thermal treatment. Key to the process is the combined use of either a strontium (Sr(2+)) or barium (Ba(2+)) catalyst with an amphiphilic molecular template. The silica nanostructure constructed by cooperative self-assembly permits homogeneous distribution of the cations, which are responsible for the crystallization of quartz. The low mismatch between the silicon and α-quartz cell parameters selects this particular polymorph, inducing epitaxial growth.
authors.affiliation: Laboratoire Chimie de la Matière Condensée, UMR UPMC-Collège de France-CNRS 7574, Collège de France, 11 Place Marcelin Berthelot, 75231 Paris, France.
authors.forename: A
authors.initials: A
authors.lastname: Carretero-Genevrier
authors.forename: M
authors.initials: M
authors.lastname: Gich
authors.forename: L
authors.initials: L
authors.lastname: Picas
authors.forename: J
authors.initials: J
authors.lastname: Gazquez
authors.forename: G L
authors.initials: GL
authors.lastname: Drisko
authors.forename: C
authors.initials: C
authors.lastname: Boissiere
authors.forename: D
authors.initials: D
authors.lastname: Grosso
authors.forename: J
authors.initials: J
authors.lastname: Rodriguez-Carvajal
authors.forename: C
authors.initials: C
authors.lastname: Sanchez