Publications by Mario Joe Lehmann

Interactions between aluminium and fired passivating contacts during fire-through metallization (vol 249, 112051, 2023)

Christophe Ballif, Aïcha Hessler-Wyser, Antoine Descoeudres, Franz-Josef Haug, Mario Joe Lehmann, Andrea Ingenito, Sofia Libraro

Elsevier2024

Interactions between aluminium and fired passivating contacts during fire-through metallization

Christophe Ballif, Aïcha Hessler-Wyser, Franz-Josef Haug, Mario Joe Lehmann, Sofia Libraro

Replacing silver metallization with earth-abundant materials in Si solar cells is a critical step towards the sustainable growth of photovoltaics. In this work, we investigate fire-through processes using Al for the metallization of solar cells with p-type ...

ELSEVIER2023

Impact of rapid thermal processing on bulk and surface recombination mechanisms in FZ silicon with fired passivating contacts

Christophe Ballif, Franz-Josef Haug, Mario Joe Lehmann, Andrea Ingenito, Sofia Libraro, Audrey Marie Isabelle Morisset

We investigate bulk and interface recombination in crystalline silicon with p-type fired passivating contacts. These consist of a chemical oxide and an in-situ doped layer of SiCx with low carbon content. Following a rapid thermal annealing to activate the ...

ELSEVIER2022

Bulk Defects and Hydrogenation Kinetics in Crystalline Silicon Solar Cells With Fired Passivating Contacts

Christophe Ballif, Philippe Wyss, Franz-Josef Haug, Mario Joe Lehmann, Père Roca i Cabarrocas, Andrea Ingenito, Audrey Marie Isabelle Morisset

In this article, the effect of the various processing steps during the fabrication of c-Si/SiOx/SiCx fired passivating contacts on the silicon bulk lifetime is studied, and the kinetics of defect deactivation by hydrogenation is investigated. It is found t ...

2022

Characterization and Development of Fired Passivating Contacts for Silicon Solar Cells

Mario Joe Lehmann

One of the key elements to improve mainstream crystalline silicon (c-Si) solar cell performance is surface passivation, which is at the center of the ongoing transition from cells with direct silicon-metal contacts to full area passivating contacts. In the ...

EPFL2022

Influence of the Dopant Gas Precursor in P-Type Nanocrystalline Silicon Layers on the Performance of Front Junction Heterojunction Solar Cells

Christophe Ballif, Quentin Thomas Jeangros, Mathieu Gérard Boccard, Jean Cattin, Luca Massimiliano Antognini, Mario Joe Lehmann, Vincent Philippe Paratte, Laurie-Lou Senaud, Jan Haschke, Julie Amandine Dreon

Silicon heterojunction solar cells can employ p-type hydrogenated nanocrystalline silicon nc-Si:H(p) on their front side, since these can provide better transparency and contact resistance compared to hydrogenated p-type amorphous silicon layers. We invest ...

2021

Evaluation of secondary electron intensities for dopant profiling in ion implanted semiconductors: a correlative study combining SE, SIMS and ECV methods

Aïcha Hessler-Wyser, Quentin Thomas Jeangros, Philippe Wyss, Franz-Josef Haug, Mario Joe Lehmann, Audrey Marie Isabelle Morisset

This study evaluates the secondary electron (SE) dopant contrast in scanning electron microscopy (SEM) and helium ion microscopy (HIM) on boron implanted silicon sample. Complementary techniques like secondary ion mass spectrometry and electrochemical capa ...

IOP PUBLISHING LTD2021

Passivating Polysilicon Recombination Junctions for Crystalline Silicon Solar Cells

Christophe Ballif, Aïcha Hessler-Wyser, Quentin Thomas Jeangros, Philippe Wyss, Franz-Josef Haug, Mario Joe Lehmann, Andrea Ingenito, Audrey Marie Isabelle Morisset

Polysilicon recombination junctions whose n-type bottom layers double as a passivating contact to the silicon surface are investigated. Such recombination junctions are a key element in the interconnection of tandem devices with a silicon bottom cell, and ...

2021

Quantification of hydrogen in nanostructured hydrogenated passivating contacts for silicon photovoltaics combining SIMS-APT-TEM: A multiscale correlative approach

Aïcha Hessler-Wyser, Quentin Thomas Jeangros, Franz-Josef Haug, Mario Joe Lehmann

Multiscale characterization of the hydrogenation process of silicon solar cell contacts based on c-Si/SiOx/ncSiCx(p) has been performed by combining dynamic secondary ion mass-spectrometry (D-SIMS), atom probe tomography (APT), and transmission electron mi ...

ELSEVIER2021

A Mixed-Phase SiOx Hole Selective Junction Compatible With High Temperatures Used in Industrial Solar Cell Manufacturing

Christophe Ballif, Quentin Thomas Jeangros, Philippe Wyss, Xavier Niquille, Franz-Josef Haug, Matthieu Despeisse, Mario Joe Lehmann, Iris Anita Mack, Gizem Nogay, Josua Andreas Stückelberger, Andrea Ingenito

We present a p-type passivating rear contact that complies with integration into standard solar cell manufacturing with phosphorus-diffused front side. Our contact structure consists of a thin SiOx tunneling layer grown by wet chemistry and a stack of laye ...

IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC2020

A method for quantitative nanoscale imaging of dopant distributions using secondary ion mass spectrometry: an application example in silicon photovoltaics

Aïcha Hessler-Wyser, Quentin Thomas Jeangros, Franz-Josef Haug, Mario Joe Lehmann, Gizem Nogay, Andrea Ingenito

A method for rapid quantitative imaging of dopant distribution using secondary ion mass spectrometry (SIMS) is described. The method is based on SIMS imaging of the cross-section of a reference sample with a known concentration profile. It is demonstrated ...

2019

Analysis of deposited layers with deuterium and impurity elements on samples from the divertor of JET with ITER-like wall

Patrick Blanchard, Basil Duval, Ambrogio Fasoli, Yves Martin, Richard Pitts, Olivier Sauter, Henri Weisen, Robin Humphry-Baker, Stefano Coda, Partha Dutta, Marco Wischmeier, Jan Horacek, Vlad Trifa, Yann Camenen, Jonathan Graves, Duccio Testa, Magalie Diane Bassan, Sun Hee Kim, Mikhail Maslov, Javier García Hernández, David Pfefferlé, Fernando Cortes Salazar, Petre Alexandru Arion, Jose Felix Vega Stavro, Lenke Horváth, Hugo Augusto Penedones Fernandes, Stéphanie Prior, Philippe Janson, Daniel Scott Alessi, Matthew Brown, Philippe Jean Buchs, Lorenzo Anton-Louis Talà, Mario Joe Lehmann, Pamela Solange Valdés Undurraga, Michael Oliver Reinke, Jonnathan Cesar Hidalgo Acosta, Wei Tang, Albano António De Abreu E Presa De Castro E Sousa, Lyne Moser, , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , ,

Tritium distributions on W-coated divertor tiles used in the third JET ITER-like wall campaign

Patrick Blanchard, Basil Duval, Ambrogio Fasoli, Yves Martin, Richard Pitts, Olivier Sauter, Henri Weisen, Robin Humphry-Baker, Stefano Coda, Partha Dutta, Marco Wischmeier, Vlad Trifa, Yann Camenen, Jonathan Graves, Duccio Testa, Magalie Diane Bassan, Sun Hee Kim, Mikhail Maslov, Javier García Hernández, David Pfefferlé, Fernando Cortes Salazar, Petre Alexandru Arion, Jose Felix Vega Stavro, Lenke Horváth, Hugo Augusto Penedones Fernandes, Stéphanie Prior, Philippe Janson, Daniel Scott Alessi, Matthew Brown, Philippe Jean Buchs, Lorenzo Anton-Louis Talà, Mario Joe Lehmann, Pamela Solange Valdés Undurraga, Michael Oliver Reinke, Jonnathan Cesar Hidalgo Acosta, Wei Tang, Albano António De Abreu E Presa De Castro E Sousa, Lyne Moser, Dalziel Joseph Wilson, , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , ,

Population modelling of the He II energy levels in tokamak plasmas: I. Collisional excitation model

Patrick Blanchard, Basil Duval, Ambrogio Fasoli, Yves Martin, Richard Pitts, Olivier Sauter, Henri Weisen, Robin Humphry-Baker, Stefano Coda, Partha Dutta, Marco Wischmeier, Jan Horacek, Vlad Trifa, Yann Camenen, Jonathan Graves, Duccio Testa, Magalie Diane Bassan, Sun Hee Kim, Mikhail Maslov, Javier García Hernández, David Pfefferlé, Fernando Cortes Salazar, Petre Alexandru Arion, Jose Felix Vega Stavro, Lenke Horváth, Hugo Augusto Penedones Fernandes, Stéphanie Prior, Philippe Janson, Daniel Scott Alessi, Matthew Brown, Philippe Jean Buchs, Lorenzo Anton-Louis Talà, Mario Joe Lehmann, Pamela Solange Valdés Undurraga, Michael Oliver Reinke, Jonnathan Cesar Hidalgo Acosta, Wei Tang, Albano António De Abreu E Presa De Castro E Sousa, Lyne Moser, , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , ,

Analysis of hydrogen distribution and migration in fired passivating contacts (FPC)

Christophe Ballif, Aïcha Hessler-Wyser, Quentin Thomas Jeangros, Philippe Wyss, Franz-Josef Haug, Matthieu Despeisse, Mario Joe Lehmann, Andrea Ingenito

High temperature passivating contacts for c-Si based solar cells are intensively studied because of their potential in boosting solar cell efficiency while being compatible with industrial processes at high temperatures. In this work, the hydrogenation mec ...

2019

Analysis and Reduction of Time Response in Thermally Activated Shape Memory Alloys

Yves Perriard, Yoan René Cyrille Civet, Mario Joe Lehmann, Raphaël Johannes Charles Mottet, Sean Thomas

This paper aims to study the factors that affect the time response of Shape Memory Alloys (SMA) and establish a method to improve their activation times. In this work, different parameters such as the number, positions and orientation of the perforations o ...

2018

Neutron spectroscopy measurements of 14 MeV neutrons at unprecedented energy resolution and implications for deuterium-tritium fusion plasma diagnostics

Patrick Blanchard, Basil Duval, Ambrogio Fasoli, Yves Martin, Richard Pitts, Olivier Sauter, Henri Weisen, Stefano Coda, Marco Wischmeier, Jan Horacek, Vlad Trifa, Yann Camenen, Jonathan Graves, Duccio Testa, Sun Hee Kim, Mikhail Maslov, Javier García Hernández, David Pfefferlé, Petre Alexandru Arion, Jose Felix Vega Stavro, Lenke Horváth, Hugo Augusto Penedones Fernandes, Stéphanie Prior, Philippe Janson, Daniel Scott Alessi, Matthew Brown, Philippe Jean Buchs, Lorenzo Anton-Louis Talà, Mario Joe Lehmann, Pamela Solange Valdés Undurraga, Jonnathan Cesar Hidalgo Acosta, Wei Tang, Albano António De Abreu E Presa De Castro E Sousa, Lyne Moser, Dalziel Joseph Wilson, Justin Robert Young, Jonathan Marc Philippe Faustin, Federico Nespoli, Alexis Gérald Page, , , , , , , , , , , , , , , , , , , , , , ,

14 MeV calibration of JET neutron detectors-phase 1: calibration and characterization of the neutron source

Patrick Blanchard, Basil Duval, Ambrogio Fasoli, Yves Martin, Richard Pitts, Olivier Sauter, Henri Weisen, Robin Humphry-Baker, Stefano Coda, Partha Dutta, Marco Wischmeier, Jan Horacek, Vlad Trifa, Yann Camenen, Jonathan Graves, Duccio Testa, Magalie Diane Bassan, Sun Hee Kim, Mikhail Maslov, Javier García Hernández, David Pfefferlé, Fernando Cortes Salazar, Petre Alexandru Arion, Jose Felix Vega Stavro, Lenke Horváth, Hugo Augusto Penedones Fernandes, Stéphanie Prior, Philippe Janson, Daniel Scott Alessi, Matthew Brown, Philippe Jean Buchs, Lorenzo Anton-Louis Talà, Mario Joe Lehmann, Pamela Solange Valdés Undurraga, Michael Oliver Reinke, Jonnathan Cesar Hidalgo Acosta, Wei Tang, Albano António De Abreu E Presa De Castro E Sousa, Lyne Moser, , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , ,

Microengineered CH3NH3PbI3 Nanowire/Graphene Phototransistor for Low-Intensity Light Detection at Room Temperature

László Forró, Richard Gaal, Arnaud Magrez, Bálint Náfrádi, Massimo Spina, Endre Horvath, Laurent Syavoch Bernard, Mario Joe Lehmann, Eric Joseph Bonvin

The first hybrid phototransistors are reported where the performance of a network of photoactive CH3NH3PbI3 nanowires is enhanced by CVD-grown monolayer graphene. These devices show responsivities as high as ≈2.6 × 106 A W- ...

2015