Publications by Jonas Geissbühler

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

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

2021

Toward Annealing-Stable Molybdenum-Oxide-Based Hole-Selective Contacts For Silicon Photovoltaics

Christophe Ballif, Stephanie Essig, Jonas Geissbühler, Mathieu Gérard Boccard, Stefaan De Wolf, Monica Morales Masis, Jérémie Werner, Philipp Friedrich Hermann Löper, Oscar Esteban Rucavado Leandro, Julie Amandine Dreon

Molybdenum oxide (MoOX) combines a high work function with broadband optical transparency. Sandwiched between a hydrogenated intrinsic amorphous silicon passivation layer and a transparent conductive oxide, this material allows a highly efficient hole‐sele ...

2018

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

Christophe Ballif, Quentin Thomas Jeangros, Antoine Descoeudres, Antonin Faes, Gabriel Christmann, Jonas Geissbühler, Matthieu Despeisse, Bertrand Yves Paul Paviet-Salomon, Stefaan De Wolf, Nicolas Badel

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

ITO/MoOx/a-Si:H(i) Hole-Selective Contacts for Silicon Heterojunction Solar Cells: Degradation Mechanisms and Cell Integration

Christophe Ballif, Davide Sacchetto, Aïcha Hessler-Wyser, Quentin Thomas Jeangros, Antoine Descoeudres, Gabriel Christmann, Jonas Geissbühler, Matthieu Despeisse, Sylvain Nicolay, Loris Barraud

Molybdenum oxide is an efficient hole collector for silicon solar cells. However, its optoelectronic properties deteriorate during cell manufacturing. To assess this issue, the optoelectronic properties and microstructure of molybdenum oxide-based hole con ...

2017

Strategies for Doped Nanocrystalline Silicon Integration in Silicon Heterojunction Solar Cells

Christophe Ballif, Aïcha Hessler-Wyser, Antoine Descoeudres, Jonas Geissbühler, Gizem Nogay, Stefaan De Wolf, Martin Ledinsky, Martial Duchamp, Johannes Peter Seif, Simon Hänni

Carrier collection in silicon heterojunction (SHJ) solar cells is usually achieved by doped amorphous silicon layers of a few nanometers, deposited at opposite sides of the crystalline silicon wafer. These layers are often defect-rich, resulting in modest ...

Ieee-Inst Electrical Electronics Engineers Inc2016

Efficient silicon solar cells with dopant-free asymmetric heterocontacts

Christophe Ballif, Jonas Geissbühler, Stefaan De Wolf

A salient characteristic of solar cells is their ability to subject photo-generated electrons and holes to pathways of asymmetrical conductivity-'assisting' them towards their respective contacts. All commercially available crystalline silicon (c-Si) solar ...

Nature Publishing Group2016

Profilometry of thin films on rough substrates by Raman spectroscopy

Christophe Ballif, Matthieu Despeisse, Bertrand Yves Paul Paviet-Salomon, Jonas Geissbühler, Andrea Tomasi, Martin Ledinsky, Stefaan De Wolf

Thin, light-absorbing films attenuate the Raman signal of underlying substrates. In this article, we exploit this phenomenon to develop a contactless thickness profiling method for thin films deposited on rough substrates. We demonstrate this technique by ...

Nature Research2016

Advanced Architectures and Processing for High-Efficiency Silicon Heterojunction Solar Cells

Jonas Geissbühler

Crystalline silicon solar cells currently represent the largest part of the photovoltaic market. In response to the demand for higher efficiency devices, silicon heterojunction technology, which merges a crystalline silicon wafer with thin amorphous silico ...

EPFL2015

Silicon Heterojunction Solar Cells With Copper-Plated Grid Electrodes: Status and Comparison With Silver Thick-Film Techniques

Christophe Ballif, Quentin Thomas Jeangros, Antoine Descoeudres, Antonin Faes, Jonas Geissbühler, Nicolas Badel, Matthieu Despeisse, Andrea Tomasi, Stefaan De Wolf, Loris Barraud

Copper electroplating is investigated and compared with common silver printing techniques for the front metallization of silicon heterojunction solar cells. We achieve smaller feature sizes by electroplating, significantly reducing optical shadowing losses ...

Ieee-Inst Electrical Electronics Engineers Inc2014

Fabrication and characterization of monolithically integrated microchannel plates based on amorphous silicon

Christophe Ballif, Jonas Geissbühler, Nicolas Würsch, Andrea Franco

Microchannel plates are vacuum-based electron multipliers for particle—in particular, photon— detection, with applications ranging from image intensifiers to single-photon detectors. Their key strengths are large signal amplification, large active area, mi ...

Nature Publishing Group2014