Publications de Libero Zuppiroli

Color conversion films comprising polymer-substituted organic fluorescent dyes

Libero Zuppiroli, Holger Frauenrath, Rolando Ferrini, Stéphane Suarez, 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

On the origin of exciton formation in dye doped Alq(3) OLEDs

Libero Zuppiroli

Electrically Detected Magnetic Resonance (EDMR) was used to investigate the influence of dye doping on spin-dependent exciton formation in aluminum (III) 8-hydroxyquinoline (Alq(3)) based Organic Light Emitting Diodes (OLEDs) with different device structur ...

Springer2012

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

The effects of channel length and film microstructure on the performance of pentacene transistors

Jürgen Brugger, Andreea Veronica Savu, Libero Zuppiroli, Katrin Sidler Arnet, Franziska Dora Fleischli

With the use of the stencil lithography, we fabricated pentacene thin-ﬁlm transistors pre- pared directly on thermally oxidized silicon gates with channel lengths ranging from 2 to 600 lm. By performing 4-probe measurements or by using the transfer line me ...

Elsevier2011

Hopping and trapping mechanisms in organic field-effect transistors

Libero Zuppiroli, Marie-Noëlle Bussac, Steven Konezny

A charge carrier in the channel of an organic field-effect transistor (OFET) is coupled to the electric polarization of the gate in the form of a surface Fröhlich polaron [N. Kirova and M. N. Bussac, Phys. Rev. B 68, 235312 (2003)]. We study the effects of ...

2010

Magnetic field effects on the conductivity of organic bipolar and unipolar devices at room temperature

Frank Nüesch, Libero Zuppiroli

Magnetic field effects on the conductivity of different types of organic devices: undoped and dye doped aluminium (III) 8-hydroxyquinoline (Alq3)-based organic light emitting diodes (OLEDs), electrononly Alq3-based diodes, and a hole-only N,N'-diphenyl-N,N ...

Elsevier2010

From oxide surface to organic transistor properties: the nature and the role of oxide gate surface defects

Libero Zuppiroli, Stéphane Suarez, Franziska Dora Fleischli

By applying various surface treatments to the oxide gate of pentacene transistors, both in vacuum (H2, O2 and Ar plasma treatments) and in aqueous solution, we were able to vary the balance between oxygen-free radicals (Si•), oxygen-centered radicals (Si−O ...

American Chemical Society2010

Organic thin-film transistors: the passivation of the dielectric-pentacene interface by dipolar self-assembled monolayers

Libero Zuppiroli, Stéphane Suarez, Franziska Dora Fleischli

In organic thin-film transistors (OTFTs), the conducting channel is located near the interface between the organic semiconductor and the oxide dielectric; this interface is crucial for transistor performance. Self-assembled monolayers (SAMs) on the interfa ...

American Chemical Society2010

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