Publications by Sylvain Nicolay

Rear textured p-type high temperature passivating contacts and their implementation in perovskite/silicon tandem cells

Christophe Ballif, Antoine Descoeudres, Sylvain Nicolay, Quentin Thomas Jeangros, Philippe Wyss, Soo-Jin Moon, Arnaud Walter, Andrea Ingenito

Silicon solar cells based on high temperature passivating contacts are becoming mainstream in the photovoltaic industry. Here, we developed a high-quality boron-doped poly-silicon hole contact. When combined with a co-processed phosphorus-doped poly-silico ...

Royal Soc Chemistry2023

22.8% full-area bifacial n-PERT solar cells with rear side sputtered poly-Si (n) passivating contact

Christophe Ballif, Sylvain Nicolay, Bertrand Yves Paul Paviet-Salomon, Andrea Ingenito, Sofia Libraro

High-temperature compatible passivating contacts based on phosphorus doped polysilicon (poly-Si(n)) on a thin silicon oxide, employed on the rear side of bifacial n-PERT like solar cells provide an efficiency increase while being compatible with current ph ...

ELSEVIER2023

Localisation of front side passivating contacts for direct metallisation of high-efficiency c-Si solar cells

Christophe Ballif, Sylvain Nicolay, Xavier Niquille, Franz-Josef Haug, Frank Meyer, Andrea Ingenito

In this work, we present the development of passivating contacts based on thin interfacial oxide/doped polysilicon for two side contacted c-Si solar cells. In the first part, we discuss our layer optimization towards direct metallisation, using firing thro ...

ELSEVIER2022

Palliating the efficiency loss due to shunting in perovskite/silicon tandem solar cells through modifying the resistive properties of the recombination junction

Christophe Ballif, Sylvain Nicolay, Gabriel Christmann, Mathieu Gérard Boccard

As the efficiency of commercial crystalline silicon solar cells approaches its maximum theoretical value, tandem architectures are becoming increasingly popular to continue the push to higher photovoltaic performances. Thin-film materials are particularly ...

2021

Advanced method for electrical characterization of carrier-selective passivating contacts using transfer-length-method measurements under variable illumination

Christophe Ballif, Antoine Descoeudres, Nicolas Badel, Sylvain Nicolay, Gabriel Christmann, Mathieu Gérard Boccard, Matthieu Despeisse, Jonas Geissbühler, Laurie-Lou Senaud, Bertrand Yves Paul Paviet-Salomon

2021

Implementation and understanding of p plus fired rear hole selective tunnel oxide passivating contacts enabling > 22% conversion efficiency in p-type c-Si solar cells

Christophe Ballif, Sylvain Nicolay, Philippe Wyss, Franz-Josef Haug, Matthieu Despeisse, Andrea Ingenito, Sofia Libraro

Passivating contacts are key enablers for high efficiency c-Si solar cells. Here, we present our latest advancement in terms of implementation and understanding in fired passivating contacts (FPC) used as rear p + passivating contact in p-type solar cells. ...

ELSEVIER2021

Optimization of front SiNx/ITO stacks for high-efficiency two-side contacted c-Si solar cells with co-annealed front and rear passivating contacts

Christophe Ballif, Sylvain Nicolay, Xavier Niquille, Franz-Josef Haug, Frank Meyer, Andrea Ingenito

In this contribution, we present an electron selective passivating contact metallised with a low temperature process to target front side applications in crystalline silicon (c-Si) solar cells. In addition to an interfacial silicon oxide (SiOx) and an in-s ...

2020

Hole-Selective Front Contact Stack Enabling 24.1%-Efficient Silicon Heterojunction Solar Cells

Christophe Ballif, Sylvain Nicolay, Mathieu Gérard Boccard, Matthieu Despeisse, Jean Cattin, Luca Massimiliano Antognini, Vincent Philippe Paratte, Laurie-Lou Senaud, Bertrand Yves Paul Paviet-Salomon, Minh Truong, Jan Haschke, Julie Amandine Dreon, Wenjie Lin

The window-layer stack limits the efficiency of both-side-contacted silicon heterojunction solar cells. We discuss here the combination of several modifications to this stack to improve its optoelectronic performance. These include the introduction of a na ...

2020

Instability of p-i-n perovskite solar cells under reverse bias

Christophe Ballif, Laura Ding, Sylvain Nicolay, Quentin Thomas Jeangros, Arnaud Walter, Florent Sahli, Peter Joseph Fiala, Chien-Jen Yang, Fan Fu, Marion Solange Madeleine Dussouillez, Ricardo Augusto Zanotto Razera, Daniel Anthony Jacobs

Partial shading can trigger permanent damage in photovoltaic modules because the illuminated solar cells drive the shaded cells into reverse bias. Under reverse bias conditions, perovskite solar cells have been shown to degrade quickly due to processes tha ...

Royal Society of Chemistry2020

Low-Temperature Screen-Printed Metallization for the Scale-Up of Two-Terminal Perovskite-Silicon Tandems

Christophe Ballif, Nicolas Badel, Antonin Faes, Jacques Levrat, Laura Ding, Sylvain Nicolay, Gabriel Christmann, Soo-Jin Moon, Arnaud Walter, Adriana Paracchino, Matthieu Despeisse, Bertrand Yves Paul Paviet-Salomon

Tandem photovoltaic devices based on perovskite and crystalline silicon (PK/c-Si) absorbers have the potential to push commercial silicon single junction devices beyond their current efficiency limit. However, their scale-up to industrially relevant sizes ...

AMER CHEMICAL SOC2019

Quantifying competitive grain overgrowth in polycrystalline ZnO thin films

Christophe Ballif, Aïcha Hessler-Wyser, Sylvain Nicolay, Arthur Brian Aebersold, Cécile Hébert, Duncan Thomas Lindsay Alexander, Lorenzo Fanni

2019

I-2 vapor-induced degradation of formamidinium lead iodide based perovskite solar cells under heat-light soaking conditions

Christophe Ballif, Sylvain Nicolay, Quentin Thomas Jeangros, Adriana Paracchino, Jérémie Werner, Léo Duchêne, Peter Joseph Fiala, Fan Fu

Over the last years, the operational stability of perovskite solar cells has been significantly improved by compositional engineering, interface modification, and improved encapsulation techniques. However, irreversible degradation is still ubiquitously ob ...

2019

Robust Electron Transport Layers via In Situ Cross-Linking of Perylene Diimide and Fullerene for Perovskite Solar Cells

Sylvain Nicolay, Jun Ho Yum, Soo-Jin Moon, Kevin Sivula, Liang Yao, Marina Caroline Michèle Caretti

While employing charge transport layers (CTLs) in optoelectronic devices including hybrid perovskite solar cells is essential for high performance, using solution-processed organic semiconductor-based CTLs poses challenges for device fabrication. Cross-lin ...

2019

Rear-emitter silicon heterojunction solar cells with atomic layer deposited ZnO:Al serving as an alternative transparent conducting oxide to In2O3:Sn

Christophe Ballif, Antoine Descoeudres, Nicolas Badel, Sylvain Nicolay, Gabriel Christmann, Matthieu Despeisse, Loris Barraud

Here high-efficiency (above 21%) large-area silicon heterojunction solar cells with atomic layer deposited ZnO:Al as front- or back-side transparent conducting oxide are demonstrated. Photoconductance decay measurements indicate that the excellent chemical ...

2019

Perovskite/Perovskite/Silicon Monolithic Triple-Junction Solar Cells with a Fully Textured Design

Christophe Ballif, Sylvain Nicolay, Quentin Thomas Jeangros, Arnaud Walter, Jérémie Werner, Florent Sahli, Björn Niesen, Fan Fu

High efficiency triple-junction solar cells are currently made of III−V semiconductors using expensive deposition methods. Perovskite/perovskite/silicon monolithic triple-junction solar cells could be a lower-cost alternative as no epitaxial growth is requ ...

2018

Fully textured monolithic perovskite/silicon tandem solar cells with 25.2% power conversion efficiency

Christophe Ballif, Laura Ding, Sylvain Nicolay, Quentin Thomas Jeangros, Davide Sacchetto, Mathieu Gérard Boccard, Matthieu Despeisse, Jérémie Werner, Florent Sahli, Loris Barraud, Raphaël Monnard, Gianluca Cattaneo, Bertrand Yves Paul Paviet-Salomon, Björn Niesen, Matthias Wolfgang Bräuninger

Tandem devices combining perovskite and silicon solar cells are promising candidates to achieve power conversion efficiencies above 30% at reasonable costs. State-of-the-art monolithic two-terminal perovskite/silicon tandem devices have so far featured sil ...

2018

Complex Refractive Indices of Cesium–Formamidinium-Based Mixed-Halide Perovskites with Optical Band Gaps from 1.5 to 1.8 eV

Christophe Ballif, Sylvain Nicolay, Quentin Thomas Jeangros, Gabriel Christmann, Arnaud Walter, Jérémie Werner, Florent Sahli, Björn Niesen, Gizem Nogay, Philipp Friedrich Hermann Löper, Matthias Wolfgang Bräuninger, Peter Joseph Fiala, Chien-Jen Yang

Cesium-formamidinium-based mixed-halide perovskite materials with optical band gaps ranging from 1.5 to 1.8 eV are investigated by variable-angle spectroscopic ellipsometry. The determined complex refractive indices are shown to depend on the fabrication p ...

2018

Piezoelectric and structural properties of c-axis textured aluminium scandium nitride thin films up to high scandium content

Paul Muralt, Sylvain Nicolay, Gabriel Christmann, Stefan Mertin

2018

Interdigitated back contact silicon heterojunction solar cells featuring an interband tunnel junction enabling simplified processing

Christophe Ballif, Antoine Descoeudres, Nicolas Badel, Benjamin Strahm, Antonin Faes, Sylvain Nicolay, Quentin Thomas Jeangros, Gabriel Christmann, Stefaan De Wolf, Matthieu Despeisse, Loris Barraud, Jonas Geissbühler, Johannes Peter Seif, Andrea Tomasi, Bertrand Yves Paul Paviet-Salomon

This paper reports on the development of an innovative back-contacted crystalline silicon solar cell with passivating contacts featuring an interband tunnel junction at its electron-collecting contacts. In this novel architecture, named "tunnel-IBC", both ...

2018

Hybrid sequential deposition process for fully textured perovskite/silicon tandem solar cells

Christophe Ballif, Laura Ding, Sylvain Nicolay, Quentin Thomas Jeangros, Soo-Jin Moon, Arnaud Walter, Davide Sacchetto, Mathieu Gérard Boccard, Matthieu Despeisse, Jérémie Werner, Florent Sahli, Loris Barraud, Raphaël Monnard, Monica Morales Masis, Gianluca Cattaneo, Bertrand Yves Paul Paviet-Salomon, Björn Niesen, Gizem Nogay, Oscar Esteban Rucavado Leandro, Matthias Wolfgang Bräuninger, Peter Joseph Fiala, Chien-Jen Yang, Fan Fu

Tandem solar cells that feature a high-bandgap perovskite cell on top of a lower bandgap silicon cell have the potential to reach efficiencies > 30%. Here, we present a versatile hybrid deposition method that yields conformal perovskite cells directly on t ...

IEEE2018