title: Flat-top and patterned-topped cone gratings for visible and mid-infrared antireflective properties.
abstract: Achieving a broadband antireflection property from material surfaces is one of the highest priorities for those who want to improve the efficiency of solar cells or the sensitivity of photo-detectors. To lower the reflectance of a surface, we are concerned with the study of the optical response of flat-top and patterned-topped cone shaped silicon gratings, based on previous work exploring pyramid gratings. Through rigorous numerical methods such as Finite Different Time Domain, we first designed several flat-top structures that theoretically demonstrate an antireflective character within the middle infrared region. From the opto-geometrical parameters such as period, depth and shape of the pattern determined by numerical analysis, these structures have been fabricated using controlled slope plasma etching processes. In order to extend the antireflective properties up to the visible wavelengths, patterned-topped cones have been fabricated as well. Afterwards, optical characterizations of several samples were carried out. Thus, the performances of the flat-top and patterned-topped cones have been compared in the visible and mid infrared range.
authors.affiliation: Aix-Marseille Université, Institut Matériaux Microélectronique Nanosciences de Provence - IM2NP, CNRS-UMR 6242, Domaine Universitaire de Saint-Jérôme, Service 231, 13397 Marseille Cedex20, France. jean-baptiste.bruckner@im2np.fr
authors.forename: Jean-Baptiste
authors.initials: JB
authors.lastname: Brückner
authors.forename: Judikaël
authors.initials: J
authors.lastname: Le Rouzo
authors.forename: Ludovic
authors.initials: L
authors.lastname: Escoubas
authors.forename: Gérard
authors.initials: G
authors.lastname: Berginc
authors.forename: Cécile
authors.initials: C
authors.lastname: Gourgon
authors.forename: Olivier
authors.initials: O
authors.lastname: Desplats
authors.forename: Jean-Jacques
authors.initials: JJ
authors.lastname: Simon