Publications by Michel Schär | EPFL Graph Search

Related publications (7)

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

Libero Zuppiroli, Stéphane Suarez, Michel Schär, 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

Ultrathin organic transistors on oxide surfaces

Frank Nüesch, Libero Zuppiroli, Marie-Noëlle Bussac, Michel Schär, Adrian von Mühlenen

We have built a model organic field-effect transistor that is basically composed of a single layer of pentacene crystal in interaction with an oxide surface. Drain and source contacts are ohmic so that the pentacene layer can carry a current density as hig ...

Deutsche Physikalische Gesellschaft & IOP Publishing Ltd2005

Thermopower measurements on pentacene transistors

Libero Zuppiroli, Marie-Noëlle Bussac, Michel Schär, Adrian von Mühlenen

We present the first thermoelectric measurements on pentacene field effect transistors. We report high values of the Seebeck coefficient at room temperature between 240 and 500 micro V/K depending on the dielectric surface treatment. These values are indep ...

2007

Doping-induced charge trapping in organic light-emitting devices

Frank Nüesch, Libero Zuppiroli, Detlef Berner, Michel Schär

By using pyran-containing donor-acceptor dyes as doping molecules in organic light-emitting devices (OLEDs), we scrutinize the effects of charge trapping and polarization induced by the guest molecules in the electro-active host material. Laser dyes 4-(dic ...

Wiley-VCH2005

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

Jürgen Brugger, Andreea Veronica Savu, Libero Zuppiroli, Katrin Sidler Arnet, Michel Schär, 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

Controlling charge-transfer at the gate interface of organic field-effect transistors

Libero Zuppiroli, Michel Schär, Mauro Castellani, Adrian von Mühlenen

The performance and charge transport characteristics of pentacene transistors with oxide gates such as SiO2 and Al2O3 have been recently shown to largely depend on the density of residual carriers due to electron acceptor defects at the oxide surface. The ...

2008

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

Libero Zuppiroli, Stéphane Suarez, Michel Schär, 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