Publications related to Protocrystalline

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

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

Indirect tail states formation by thermal-induced polar fluctuations in halide perovskites

Michael Graetzel, Nripan Mathews, Qiang Xu, Bing Wu

Halide perovskites possess enormous potential for various optoelectronic applications. Presently, a clear understanding of the interplay between the lattice and electronic effects is still elusive. Specifically, the weakly absorbing tail states and dual em ...

Springer2019

Low Temperature p-type Microcrystalline Silicon as Carrier Selective Contact for Silicon Heterojunction Solar Cells

Christophe Ballif, Raphaël Monnard, Mathieu Gérard Boccard, Angela Nicole Fioretti

Silicon heterojunction (SHJ) solar cells have reached record efficiency, particularly in all-back-contacted architectures. Despite this, two-side contacted SHJ cells still suffer from parasitic absorption and series resistance losses in the amorphous silic ...

2019

RF bias to suppress post-oxidation of mu c-Si:H films deposited by inductively-coupled plasma using a planar RF resonant antenna

Ivo Furno, Alan Howling, Philippe Frédérique Bruno Guittienne, Rémy Jacquier

One challenge for microcrystalline silicon (mu c-Si:H) deposition is to achieve high deposition rates while maintaining high quality films. In this work, an inductively-coupled plasma (ICP) is used to deposit mu c-Si:H on glass substrates by means of a nov ...

2018

Full-Area Passivating Contacts with High and Low Thermal Budgets: Solutions for High Efficiency c-Si Solar Cells

Gizem Nogay

Today more than 90% of the global PV market is covered by c-Si solar cells which are limited by recombination losses at the metal-semiconductor interface. This recombination path can be avoided by separating the metal from the c-Si wafer by introducing a b ...

EPFL2018

Nanocrystalline Boron-Doped Diamond as a Corrosion-Resistant Anode for Water Oxidation via Si Photoelectrodes

Kevin Sivula, Jun Ho Yum, Ladislav Kavan, Florian Le Formal, Petr Ashcheulov

Due to its high sensitivity to corrosion, the use of Si in direct photoelectrochemical (PEC) water-splitting systems that convert solar energy into chemical fuels has been greatly limited. Therefore, the development of low-cost materials resistant to corro ...

AMER CHEMICAL SOC2018

Raising the one-sun conversion efficiency of III-V/Si solar cells to 32.8% for two junctions and 35.9% for three junctions

Christophe Ballif, Stephanie Essig, Antoine Descoeudres, Matthieu Despeisse, Loris Barraud

Today's dominant photovoltaic technologies rely on single-junction devices, which are approaching their practical efficiency limit of 25-27%. Therefore, researchers are increasingly turning to multi-junction devices, which consist of two or more stacked su ...

Nature Publishing Group2017

Explaining Morphological and Electrical Features of Boron-doped Zinc Oxide to Tailor New Electrodes for Photovoltaics

Lorenzo Fanni

TCOs are a class of metal oxides that combine transparency to visible light with electrical conductivity. Each TCO is characterized by the trade-off of these two properties which can be tuned for a particular application. This thesis is dedicated to the in ...

EPFL2016

Transparent Electrodes in Silicon Heterojunction Solar Cells: Influence on Contact Passivation

Christophe Ballif, Florent Sahli, Bertrand Yves Paul Paviet-Salomon, Sylvain Nicolay, Stefaan De Wolf, Johannes Peter Seif, Andrea Tomasi, Lorenzo Fanni, Björn Niesen, Loris Barraud, Silvia Martin de Nicolas Agut

Charge carrier collection in silicon heterojunction solar cells occurs via intrinsic/doped hydrogenated amorphous silicon layer stacks deposited on the crystalline silicon wafer surfaces. Usually, both the electron and hole collecting stacks are externally ...

Ieee-Inst Electrical Electronics Engineers Inc2016

Energy Yield and Electricity Management of Thin-Film and Crystalline Silicon Solar Cells : from Devices to Systems

Yannick Samuel Riesen

In the case of high photovoltaic (PV) penetration into the electricity grid, the energy produced by a PV system that is effectively used (useful energy) depends on the energy yield and on how this energy is managed to avoid detrimental effects occurring at ...

EPFL2016

High-efficiency crystalline silicon solar cells: status and perspectives

Corsin Battaglia, Stefaan De Wolf

With a global market share of about 90%, crystalline silicon is by far the most important photovoltaic technology today. This article reviews the dynamic field of crystalline silicon photovoltaics from a device-engineering perspective. First, it discusses ...

Royal Society of Chemistry2016

Silver versus white sheet as a back reflector for microcrystalline silicon solar cells deposited on LPCVD-ZnO electrodes of various textures

Christophe Ballif, Franz-Josef Haug, Mathieu Gérard Boccard, Etienne Antoine Julien Moulin

We compare the performance of two back reflector designs on the optoelectrical properties of microcrystalline silicon solar cells. The first one consists of a 5-mu m-thick low-pressure chemical vapor deposition (LPCVD)-ZnO electrode combined with a white s ...

Wiley-Blackwell2015

Highly transparent modulated surface textured front electrodes for high-efficiency multijunction thin-film silicon solar cells

Christophe Ballif, Franz-Josef Haug, Michael Elias Stückelberger, Etienne Antoine Julien Moulin, Hairen Tan

To further increase the efficiency of multijunction thin-film silicon (TF-Si) solar cells, it is crucial for the front electrode to have a good transparency and conduction, to provide efficient light trapping for each subcell, and to ensure a suitable morp ...

Wiley-Blackwell2015

Facile preparation of micron- and nano-scale textured master for nano-imprinting front electrode in thin-film silicon tandem cells with improved light trapping

Christophe Ballif, Franz-Josef Haug, Etienne Antoine Julien Moulin, Jinhua Huang

This paper reports a facile method to prepare a textured surface with combined micron- and nano-scale surface features, which is used as master for nano-imprinting process to obtain transparent front electrodes in thin-film silicon tandem cells. The micron ...

Elsevier2015

Light trapping in solar cells: numerical modeling with measured surface textures

Christophe Ballif, Franz-Josef Haug, Mathieu Gérard Boccard, Beat Ruhstaller, Thomas Andreas Lanz

We present and experimentally validate a computational model for the light propagation in thin-film solar cells that integrates non-paraxial scalar diffraction theory with non-sequential ray-tracing. The model allows computing the spectral layer absorbance ...

Optical Society of America2015

High Yield of GaAs Nanowire Arrays on Si Mediated by the Pinning and Contact Angle of Ga

Anna Fontcuberta i Morral, Federico Matteini, Gözde Tütüncüoglu, Eleonora Russo, Sonia Conesa Boj, Anna Dalmau Mallorquí, Heidi Andrea Potts, Jelena Vukajlovic Plestina

GaAs nanowire arrays on Silicon offer great perspectives in the :optoeleetronics and solar cell industry. To fulfill this potential, gold-free growth in predetermined positions should be achieved. Ga-assisted growth of GaAs nano-wires in the form of array ...

American Chemical Society2015

Light trapping in thin-film solar cells measured by Raman spectroscopy

Christophe Ballif, Grégory Bugnon, Etienne Antoine Julien Moulin, Martin Ledinsky

In this study, Raman spectroscopy is used as a tool to determine the light-trapping capability of textured ZnO front electrodes implemented in microcrystalline silicon (mu c-Si:H) solar cells. Microcrystalline silicon films deposited on superstrates of var ...

American Institute of Physics2014

Post-deposition treatment of microcrystalline silicon solar cells for improved performance on rough superstrates

Christophe Ballif, Mathieu Gérard Boccard, Sylvain Nicolay, Laura Ding, Grégory Bugnon

In this contribution, we investigate the effect of post-deposition treatments on finished non-encapsulated thin-film microcrystalline silicon solar cells and show that annealing in vacuum leads to improved electrical properties of the solar cells, particul ...

American Institute of Physics2014

High-Stable-Efficiency Tandem Thin-Film Silicon Solar Cell With Low-Refractive-Index Silicon-Oxide Interlayer

Christophe Ballif, Xavier Niquille, Matthieu Despeisse, Mathieu Gérard Boccard, Jordi Escarre Palou, Grégory Bugnon, Maximilien Joseph Marie Bonnet-Eymard

We report the recent advances and key requirements for high-efficiency "micromorph" tandem thin-film silicon solar cells composed of an amorphous silicon top cell and a microcrystalline silicon bottom cell. The impact of inserting a low-refractive-index si ...

Ieee-Inst Electrical Electronics Engineers Inc2014

Silicon oxide buffer layer at the p-i interface in amorphous and microcrystalline silicon solar cells

Christophe Ballif, Matthieu Despeisse, Gaetano Parascandolo, Grégory Bugnon, Michael Elias Stückelberger, Mathieu Charrière

The use of intrinsic silicon oxide as a buffer layer at the p-i interface of thin-film silicon solar cells is shown to provide significant advantages. For microcrystalline silicon solar cells, when associated with highly crystalline i-layers deposited at h ...

Elsevier2014