Publications by Rolando Ferrini

Optical-stack optimization for improved SPAD photon detection efficiency

Claudio Bruschini, Rolando Ferrini, Edoardo Charbon, Frédéric Zanella, Marc Schnieper, Scott Anthony Lindner, Ivan Michel Antolovic, Arin Can Ülkü, Ekin Kizilkan

Single-photon avalanche diodes (SPADs) are direct photon-to-digital detectors that enable scalable arrays with Poisson-limited signal-to-noise ratio and picosecond timing resolution. However, SPAD detectors require a guard-ring structure to prevent lateral ...

2019

Submicrometer Organic Thin-Film Transistors: Technology Assessment Through Noise Margin Analysis of Inverters

Christian Enz, Jean-Michel Sallese, Rolando Ferrini, Frédéric Zanella, Nenad Marjanovic, Franz Xaver Pengg

In this paper, we propose a methodology to evaluate the potential of submicrometer organic thin-film transistors (OTFTs) with nanoimprinted gate and self-aligned source and drain contacts. In the first step, the dedicated static model we previously reporte ...

Institute of Electrical and Electronics Engineers2014

Design and modeling of self-aligned nano-imprinted sub-micrometer pentacene-based organic thin-film transistors

Christian Enz, Jean-Michel Sallese, Randoald Müller, Rolando Ferrini, Frédéric Zanella, Nenad Marjanovic

Sub-micrometer channel length (0.5 mu m) organic thin-film transistors (OTFTs) are demonstrated using a process flow combining nano-imprint lithography (NIL) and self-alignment (SA). A dedicated test structure was designed and samples were fabricated on 4- ...

Elsevier2013

Color conversion films comprising polymer-substituted organic fluorescent dyes

Libero Zuppiroli, Rolando Ferrini, Stéphane Suarez, Holger Frauenrath, Roman Niklaus Marty

The present invention concerns a color conversion film comprising at least one active layer, said layer comprising an organic fluorescent dye containing a fluorescent core, wherein said dye is substituted with at least one polymer segment. It also concerns ...

2012

Low-loss polymer waveguides on nanoporous layers

Libero Zuppiroli, Rolando Ferrini, Gaëtan Wicht

Multimode planar polymer waveguides were fabricated on hybrid polymer nanoporous layers with a fast industrial aqueous-based method well adapted to coat large-surface plastic substrates and easily scalable up to economical mass production volumes. Using a ...

American Institute of Physics2011

Nanoporous films with low refractive index for large-surface broad-band anti-reflection coatings

Libero Zuppiroli, Rolando Ferrini, Gaëtan Wicht

Nowadays, nanoporous films are widely employed in biochemical applications or in opto-photonic devices such as displays, solar cells, or light-guiding systems. In particular, the technological feasibility of nanoporous layers with low refractive indices ha ...

Wiley-Blackwell2010

Fluorescent nanopigments: Quantitative assessment of their quantum yield

Libero Zuppiroli, Rolando Ferrini

In the last few years, an intense research effort has focused on the synthesis of fluorescent nanopigments for functional inks, light harvesting, tagging, tracing, (bio)labeling, imaging, and lighting applications. Moreover, combined with dielectric matric ...

American Institute of Physics2010

Quantum Yield Measurement of Fluorescent Zeolite Nanopigments

Libero Zuppiroli, Rolando Ferrini

Organic fluorescent molecules are infiltrated in the channels of zeolite L nanocrystals, thus creating organic-inorganic fluorescent nanoparticles. Combined with dielectric matrices, these fluorescent nanopigments open the way to the realization of novel o ...

Wiley-Blackwell2009

Local infiltration of planar photonic crystals with UV-curable polymers

Romuald Houdré, Libero Zuppiroli, Rolando Ferrini, Laurent Balet, Pascale El-Kallassi

We present the local polymer infiltration of planar photonic crystal cavities via a maskless laser-writing technique. After the infiltration of the air holes with a UV-curable monomer a focused laser is used to locally polymerize the monomer in selected ho ...

2008

Impact of feature-size dependent etching on the optical properties of photonic crystal devices

Romuald Houdré, Rolando Ferrini

Feature size dependence in Ar/Cl2 chemically assisted ion beam etching of InP-based photonic crystals (PhCs) and its influence on the optical properties of PhC devices operating in the band gap are investigated. The analysis of the measured quality factors ...

2008

Optisches Element und Verfahren zu seiner Herstellung (Optical element and methods for its fabrication)

Libero Zuppiroli, Rolando Ferrini

Applicant: ILFORD Imaging Switzerland GmbH; Designated countries: all; Filing date: September 12, 2008. ...

2008

Local tuning of the optical response of two-dimensional photonic crystals

Romuald Houdré, Libero Zuppiroli, Rolando Ferrini, Laurent Balet, Pascale El-Kallassi

Local tuning of the optical response of GaAs-based two dimensional photonic crystals (PhCs) is reported. A selective polymer infiltration technique was developed. Scanning electron microscopy and optical measurements were used to characterize the filled Ph ...

Eindhoven University of Technology2008

Hybrid inorganic-organic photonic devices

Romuald Houdré, Libero Zuppiroli, Rolando Ferrini, Laurent Balet, Nicolas Le Thomas, Pascale El-Kallassi

We present the infiltration of semiconductor photonic devices with organic materials. The infiltration procedures are described and validated. In particular, the optical properties of hybrid photonic crystal cavities are studied. ...

EOS2008

Optical tuning of planar photonic crystals infiltrated with organic molecules

Romuald Houdré, Libero Zuppiroli, Rolando Ferrini, Nicolas Le Thomas, Pascale El-Kallassi

The optical tuning of InP-based planar photonic crystals (PhCs) infiltrated with a photo-responsive liquid crystal system is presented. Photo-induced phase transitions of a liquid crystal blend doped with azobenzene molecules are used to tune the optical r ...

2007

Characterization of the feature-size dependence in Ar/Cl2 chemically assisted ion beam etching of InP-based photonic crystal devices

Romuald Houdré, Rolando Ferrini

The authors address feature-size dependence in Ar/Cl2 chemically assisted ion beam etching (CAIBE) in the context of the fabrication of photonic crystal (PhC) structures. They systematically investigate the influence of various parameters such a ...

2007

Planar photonic crystals infiltrated with liquid crystals: optical characterization of molecule orientation

Romuald Houdré, Libero Zuppiroli, Rolando Ferrini, Barbara Wild, Liza Carol Andrea Dunbar, Vasily Zabelin

Nematic liquid crystals are infiltrated into InP-based planar photonic crystals. Optical measurements as a function of temperature and polarization are used to study the average director field configuration in the nanometer-size holes: a planar equilibrium ...

Opt. Soc. America2006

Disorder-induced losses in planar photonic crystals

Romuald Houdré, Rolando Ferrini, David Leuenberger, Henri Benisty

The phenomenological approach introduced by Benisty et al. [Appl. Phys. Lett. 76, 532 (2000)] to model out-of-plane radiation losses in planar photonic crystals with a low vertical refractive index contrast is extended to the case of in-plane disorder. The ...

2006

Liquid crystal infiltration of InP-based planar photonic crystals

Romuald Houdré, Frank Nüesch, Libero Zuppiroli, Rolando Ferrini, Barbara Wild, Liza Carol Andrea Dunbar

A procedure for the infiltration of planar photonic crystals (PhCs) with liquid crystals (LCs) is presented. InP-based PhCs are infiltrated with the nematic LC-K15 in a specially designed high-vacuum chamber. The infiltration technique is validated and sys ...

AIP2006

Planar photonic crystals infiltrated with liquid crystals: tuning of the optical properties

Romuald Houdré, Libero Zuppiroli, Rolando Ferrini, Liza Carol Andrea Dunbar, Nicolas Le Thomas

2006

Feature size effects in chemically assisted ion beam etching of InP-based photonic crystals

Romuald Houdré, Rolando Ferrini

This work addresses feature size effects (the lag-effect and roughness development) in chemically assisted ion beam etching (CAIBE) etching of InP-based photonic crystals. Photonic crystal fields with varying hole size and periods were etched with differen ...

International Society for Optical Engineering, Bellingham WA, WA 98227-0010, United States2006