title: Control of the Pore Texture in Nanoporous Silicon via Chemical Dissolution.
abstract: The surface and textural properties of porous silicon (pSi) control many of its physical properties essential to its performance in key applications such as optoelectronics, energy storage, luminescence, sensing, and drug delivery. Here, we combine experimental and theoretical tools to demonstrate that the surface roughness at the nanometer scale of pSi can be tuned in a controlled fashion using partial thermal oxidation followed by removal of the resulting silicon oxide layer with hydrofluoric acid (HF) solution. Such a process is shown to smooth the pSi surface by means of nitrogen adsorption, electron microscopy, and small-angle X-ray and neutron scattering. Statistical mechanics Monte Carlo simulations, which are consistent with the experimental data, support the interpretation that the pore surface is initially rough and that the oxidation/oxide removal procedure diminishes the surface roughness while increasing the pore diameter. As a specific example considered in this work, the initial roughness ξ ∼ 3.2 nm of pSi pores having a diameter of 7.6 nm can be decreased to 1.0 nm following the simple procedure above. This study allows envisioning the design of pSi samples with optimal surface properties toward a specific process.
authors.affiliation: †UMR 5253 CNRS/UM/ENSCM, Institut Charles Gerhardt Montpellier, 8 rue de l'Ecole Normale, 34296 Montpellier, France.
authors.forename: Emilie
authors.initials: E
authors.lastname: Secret
authors.affiliation: ‡Department of Chemistry and Biochemistry, University of California, San Diego, La Jolla, California 92093-0358, United States.
authors.forename: Chia-Chen
authors.initials: CC
authors.lastname: Wu
authors.affiliation: †UMR 5253 CNRS/UM/ENSCM, Institut Charles Gerhardt Montpellier, 8 rue de l'Ecole Normale, 34296 Montpellier, France.
authors.forename: Arnaud
authors.initials: A
authors.lastname: Chaix
authors.affiliation: †UMR 5253 CNRS/UM/ENSCM, Institut Charles Gerhardt Montpellier, 8 rue de l'Ecole Normale, 34296 Montpellier, France.
authors.forename: Anne
authors.initials: A
authors.lastname: Galarneau
authors.affiliation: †UMR 5253 CNRS/UM/ENSCM, Institut Charles Gerhardt Montpellier, 8 rue de l'Ecole Normale, 34296 Montpellier, France.
authors.forename: Philippe
authors.initials: P
authors.lastname: Gonzalez
authors.affiliation: §ENSCM/UM2/UMR 5635, Institut Européen des Membranes, Place Eugène Bataillon CC 047, 34095 Montpellier, France.
authors.forename: Didier
authors.initials: D
authors.lastname: Cot
authors.affiliation: ‡Department of Chemistry and Biochemistry, University of California, San Diego, La Jolla, California 92093-0358, United States.
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Sailor
authors.affiliation: ∥Laboratoire Leon Brillouin, CEA-Saclay, 91191 Gif sur Yvette Cedex, France.
authors.forename: Jacques
authors.initials: J
authors.lastname: Jestin
authors.affiliation: ∥Laboratoire Leon Brillouin, CEA-Saclay, 91191 Gif sur Yvette Cedex, France.
authors.forename: Jean-Marc
authors.initials: JM
authors.lastname: Zanotti
authors.affiliation: †UMR 5253 CNRS/UM/ENSCM, Institut Charles Gerhardt Montpellier, 8 rue de l'Ecole Normale, 34296 Montpellier, France.
authors.forename: Frédérique
authors.initials: F
authors.lastname: Cunin
authors.affiliation: †UMR 5253 CNRS/UM/ENSCM, Institut Charles Gerhardt Montpellier, 8 rue de l'Ecole Normale, 34296 Montpellier, France.|⊥MultiScale Materials Science for Energy and Environment, CNRS/MIT (UMI 3466), 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States.|#Department of Civil and Environmental Engineering, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States.
authors.forename: Benoit
authors.initials: B
authors.lastname: Coasne
mesh_terms: D006858:Hydrofluoric Acid / Q000737:chemistry; D009010:Monte Carlo Method; D016062:Porosity; D012825:Silicon / Q000737:chemistry*; D012995:Solubility; D013499:Surface Properties
chemical_list: D006858:Hydrofluoric Acid; D012825:Silicon