Publications associées à Dopant

Surfactant behavior and limited incorporation of indium during in situ doping of GeSn grown by molecular beam epitaxy

Anna Fontcuberta i Morral, Andrea Giunto, Thomas Hagger, Louise Emma Webb

GeSn is a promising group-IV semiconductor material for on-chip Si photonics devices and high-mobility transistors. These devices require the use of doped GeSn regions, achieved preferably in situ during epitaxy. From the electronic valence point of view, ...

AMER PHYSICAL SOC2023

Dynamic Nuclear Polarization of Inorganic Halide Perovskites

David Lyndon Emsley, Dominik Józef Kubicki, Gabriele Stevanato, Michael Allan Hope, Aditya Mishra

The intrinsic low sensitivity of nuclear magnetic resonance (NMR) experiments limits their utility for structure determination of materials. Dynamic nuclear polarization (DNP) under magic angle spinning (MAS) has shown tremendous potential to overcome this ...

2023

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

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

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

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, Laurie-Lou Senaud, Jan Haschke, Luca Massimiliano Antognini, Jean Cattin, Julie Amandine Dreon, Mario Joe Lehmann, Vincent Philippe Paratte

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

Luminescent lanthanide nanocomposites in thermometry: Chemistry of dopant ions and host matrices

Mohammad Khaja Nazeeruddin

Recently, there has been observed huge progress in the advancement of remote optical nanothermometry, as it plays a vital role in remote, noninvasive, and remote temperature sensing, which is especially important for various bio-applications, e.g., in ther ...

ELSEVIER SCIENCE SA2021

Importance of Long-Range Channel Sr Displacements for the Narrow Emission in Sr[Li2Al2O2N2]:Eu2+ Phosphor

Samuel Poncé

The recently discovered Sr[Li2Al2O2N2]:Eu2+ red phosphor, candidate for the next generation of eco-efficient white light-emitting diodes, exhibits excellent emission spectral position and exceptionally small linewidth. It belongs to the UCr4C4-structure fa ...

WILEY-V C H VERLAG GMBH2021

Accelerating materials discovery for solid state electrolytes

Matthieu Gilles Mottet

The development of new solid-state electrolytes is a key step in improving the performance and safety of battery technology. Although the use of first-principle methods has proved invaluable in better understanding the process at play in these materials, ...

EPFL2020

Scalable Nanowire Networks: Growth and Functionality

Martin George Friedl

With the rise of quantum computing and recent experiments into topological quantum computers come exciting new opportunities for III-V semiconductor quantum nanostructures. In this thesis, we explore the scalable fabrication of patterned arrays and branche ...

EPFL2020

Radio-Frequency Characteristics of Ge-doped Vanadium Dioxide Thin Films with Increased Transition Temperature

Mihai Adrian Ionescu, Andreas Schueler, Igor Stolichnov, Anna Krammer, Teodor Rosca, Matteo Cavalieri, Riyaz Mohammed Abdul Khadar, Andrei Müller, Fatemeh Qaderi Rahaqi

This work investigates and reports on the radio-frequency (RF) behavior in the frequency range of 5 – 35 GHz of germanium-doped (Ge-doped VO2) vanadium dioxide thin films, deposited on silicon substrates via sputtering and pulsed laser deposition (PLD) wit ...

2020

Elucidating the Doping Mechanism in Fluorene-Dithiophene-Based Hole Selective Layer Employing Ultrahydrophobic Ionic Liquid Dopant

Mohammad Khaja Nazeeruddin, Sanghyun Paek, Tom Theodorus Antonius Lummen, Laura Calio

Perovskite solar cells have set a new milestone in terms of efficiencies in the thin film photovoltaics category. Long-term stability of perovskite solar cells is of paramount importance but remains a challenging task. The lack of perovskite solar cells st ...

2020

Polarity-Controllable Devices and Circuits for Doping-Free 2D Electronics

Giovanni Vincenzo Resta

The growth of information technology has been sustained by the miniaturization of Complementary Metal-Oxide-Semiconductor (CMOS) Field-Effect Transistors (FETs), with the number of devices per unit area constantly increasing, as exemplified by Mooreâ s la ...

EPFL2019

Template-assisted grown III-V semiconductor nanowires: A transmission electron microscopy study

Nicolas Bologna

III-V semiconductor nanowires are, due to their unique properties, one of the most promising nanostructures developed in the last decades. However, the realization of commercial devices made of III-V nanowires, such as transistors and solar cells, has not ...

EPFL2019

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

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

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

A multi-technique approach to study the microstructural properties of tin-based transparent conductive oxides

Federica Landucci

Transparent conductive oxides (TCOs) are semiconductor-like materials that exhibit high electrical conductivity and high optical transparency combined. They are adopted in various applications ranging from gas sensors, to electrochromic windows, to photovo ...

EPFL2019

Novel p-dopant toward highly efficient and stable perovskite solar cells

Michael Graetzel, Shaik Mohammed Zakeeruddin, Ulf Anders Hagfeldt, Jiyoun Seo, Hui-Seon Kim, Seckin Akin, Marko Stojanovic

Li-TFSI is the most common p-dopant for the hole conductor spiro-MeOTAD in the normal structure (n-i-p) of perovskite solar cells (PSCs), which consistently yield the highest power conversion efficiency (PCE) albeit at the risk of lower long-term operation ...

ROYAL SOC CHEMISTRY2018

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, Sylvain Nicolay, Benjamin Strahm, Andrea Tomasi, Loris Barraud, Johannes Peter Seif

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

Direct Imaging of Dopant Distribution in Polycrystalline ZnO Films

Christophe Ballif, Aïcha Hessler-Wyser, Cécile Hébert, Sylvain Nicolay, Duncan Thomas Lindsay Alexander, Martin Ledinsky, Stéphane Laurent Escrig, Monica Morales Masis, Arthur Brian Aebersold

Two fundamental requirements of transparent conductive oxides are high conductivity and low optical absorptance, properties strongly dependent on the free-carrier concentration of the film. The free carrier concentration is usually-tuned by the addition of ...

Amer Chemical Soc2017

Stabilization of the Perovskite Phase of Formamidinium Lead Triiodide by Methylammonium, Cs, and/or Rb Doping

Ursula Röthlisberger, Michael Saliba, Olga Syzgantseva

In this work we perform a computational study comparing the influence of monovalent cation substitution by methylammonium (MA(+)), cesium (Cs+), and rubidium (Rb+) on the properties of formamidinium lead triiodide (FAPbI(3))based perovskites. The relative ...

2017

Migration of Mg and other interstitial metal dopants in GaN

Alfredo Pasquarello, Giacomo Francesco Leonardo Miceli

The minimumenergy paths for the migration of interstitialMgin wurtziteGaNare studiedthroughdensityfunctional calculations. The study also comprises Li, Na, and Be dopants to examine the dependence on size and charge of the dopant species. In all cases cons ...

Wiley-Blackwell2017

Dual-Emission Band All-Fiber Laser based on Theta Cavity with Thulium- and Holmium-Doped Fibers

Camille Sophie Brès, Svyatoslav Kharitonov

We present first dual-wavelength all-fiber laser, based on isolator-free theta cavity with two fiber Bragg mirrors and thulium- and holmium-doped fibers. Laser provides 350mW total power with 8% slope efficiency, and linewidth less than 01.mm. ...

Ieee2017