Publications de Sylvain Dunand

Hydrogenated Amorphous Silicon Charge-Selective Contact Devices on a Polyimide Flexible Substrate for Dosimetry and Beam Flux Measurements

Sylvain Dunand, Nicolas Würsch, Jonathan Emanuel Thomet

Hydrogenated amorphous silicon (a-Si:H) devices on flexible substrates are currently being studied for application in dosimetry and beam flux measurements. The necessity of in vivo dosimetry requires thin devices with maximal transparency and flexibility. ...

MDPI2025

Cleopatra: a 12-channel recycling integrator ASIC for the readout of hydrogenated amorphous silicon detectors in radiotherapy dosimetry

Sylvain Dunand, Nicolas Würsch, Jonathan Emanuel Thomet

The Cleopatra ASIC is a 12-channel prototype ASIC for the readout of hydrogenated amorphous silicon sensors used for real-time dosimetry in radiation diagnostic and radiation therapy. The architecture is based on a current to frequency conversion based on ...

2025

HASPIDE: a project for the development of hydrogenated amorphous silicon radiation sensors on a flexible substrate

Giovanni De Cesare, Luca Massimiliano Antognini, Sylvain Dunand, Mikaël Martino, Jonathan Emanuel Thomet, Matthew James Large

Hydrogenated amorphous silicon (a-Si:H) is a material with a very good radiation hardness and with the possibility of deposition on flexible substrates like Polyimide (PI). Exploiting these properties, the HASPIDE (Hydrogenated Amorphous Silicon PIxels DEt ...

Iop Publishing Ltd2024

A Front-End Circuit in 28 nm CMOS for Hydrogenated Amorphous Silicon Detectors in Clinical Dosimetry

Sylvain Dunand, Nicolas Würsch, Luca Massimiliano Antognini, Jonathan Emanuel Thomet

This paper presents the design and the characterization of a front-end circuit, designed in 28 nm CMOS, for real-time dosimetry in radiation diagnostics and radiation therapy. The front-end circuit is optimized for sensors made of hydrogenated amorphous si ...

Institute of Electrical and Electronics Engineers Inc.2024

Dosimetry of microbeam radiotherapy by flexible hydrogenated amorphous silicon detectors

Sylvain Dunand, Nicolas Würsch, Jonathan Emanuel Thomet

Objective. Detectors that can provide accurate dosimetry for microbeam radiation therapy (MRT) must possess intrinsic radiation hardness, a high dynamic range, and a micron-scale spatial resolution. In this work we characterize hydrogenated amorphous silic ...

IOP Publishing Ltd2024

Mobility Gaps of Hydrogenated Amorphous Silicon Related to Hydrogen Concentration and Its Influence on Electrical Performance

Sylvain Dunand, Nicolas Würsch, Jonathan Emanuel Thomet

This paper presents a comprehensive study of hydrogenated amorphous silicon (a-Si)-based detectors, utilizing electrical characterization, Raman spectroscopy, photoemission, and inverse photoemission techniques. The unique properties of a-Si have sparked i ...

2024

Amorphous silicon detectors for proton beam monitoring in FLASH radiotherapy

Christophe Ballif, Sylvain Dunand, Nicolas Würsch, Luca Massimiliano Antognini, Jonathan Emanuel Thomet

Ultra-high dose rate radiation therapy (FLASH) based on proton irradiation is of major interest for cancer treatments but creates new challenges for dose monitoring. Amorphous hydrogenated silicon is known to be one of the most radiation-hard semiconductor ...

Elsevier BV2024

Characterization of Hydrogenated Amorphous Silicon Sensors on Polyimide Flexible Substrate

Sylvain Dunand, Nicolas Würsch, Jonathan Emanuel Thomet

Hydrogenated amorphous silicon (a-Si:H) is a material having an intrinsically high radiation hardness that can be deposited on flexible substrates such as polyimide (PI). For these properties, a-Si:H can be used for the production of flexible sensors. a-Si ...

2024

Characterization of a flexible a-Si:H detector for in vivo dosimetry in therapeutic x-ray beams

Sylvain Dunand, Nicolas Würsch, Luca Massimiliano Antognini, Jonathan Emanuel Thomet, Matthew James Large

BackgroundThe increasing use of complex and high dose-rate treatments in radiation therapy necessitates advanced detectors to provide accurate dosimetry. Rather than relying on pre-treatment quality assurance (QA) measurements alone, many countries are now ...

Wiley2024

TCAD modelling of a-Si:H devices for particle detection applications

Sylvain Dunand, Nicolas Würsch, Luca Massimiliano Antognini, Matthew James Large, Giulia Rossi

Hydrogenated amorphous silicon (a-Si:H) has been proposed as a suitable material for particle detection applications thanks to its property to be deposited over a large area and above a variety of different substrates, including flexible materials. Moreove ...

Elsevier Sci Ltd2023