Publications by Philipp Friedrich Hermann Löper

Nanoscale Study of the Hole-Selective Passivating Contacts with High Thermal Budget Using C-AFM Tomography

Christophe Ballif, Franz-Josef Haug, Quentin Thomas Jeangros, Gizem Nogay, Philipp Friedrich Hermann Löper, Martin Ledinsky

We investigate hole-selective passivating contacts that consist of an interfacial layer of silicon oxide (SiOx) and a layer of boron-doped SiCx(p). The fabrication process of these contacts involves an annealing step at temperatures above 750 degrees C whi ...

AMER CHEMICAL SOC2021

Numerical simulations of hole carrier selective contacts in p-type c-Si solar cells

Christophe Ballif, Andrea Ingenito, Philipp Friedrich Hermann Löper

This work presents a systematic analysis of the transport mechanism and surface passivation of tunneling oxide (SiO2)/p-type poly-silicon (poly-Si(p)) junctions applied to p-type crystalline silicon (c-Si) solar cells by means of TCAD numerical simulations ...

ELSEVIER2019

Phosphorous-Doped Silicon Carbide as Front-Side Full-Area Passivating Contact for Double-Side Contacted c-Si Solar Cells

Christophe Ballif, Andrea Ingenito, Franz-Josef Haug, Matthieu Despeisse, Gizem Nogay, Philipp Friedrich Hermann Löper, Philippe Wyss, Josua Andreas Stückelberger, Luca Gnocchi

We present an electron selective passivating contact based on a tunneling SiOx capped with a phosphorous doped siliconcarbideandpreparedwithahigh-temperaturethermalanneal. We investigate in detail the effects of the preparation conditions of theSiCx(n)(i.e ...

2018

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

Christophe Ballif, Jérémie Werner, Quentin Thomas Jeangros, Matthias Wolfgang Bräuninger, Gabriel Christmann, Florent Sahli, Arnaud Walter, Sylvain Nicolay, Björn Niesen, Gizem Nogay

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

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

Silicon heterojunction solar cells and methods of manufacture

Christophe Ballif, Andrea Ingenito, Gizem Nogay, Philipp Friedrich Hermann Löper

The present invention relates to a solar cell comprising a heterojunction photoelectric device comprising, a front electrode layer, a back electrode layer comprising a metallic contact layer (300), a light-absorbing silicon layer (1 ) arranged between said ...

2018

Carrier injection from amorphous silicon into crystalline silicon determined with photoluminescence

Andrea Ingenito, Gizem Nogay, Philipp Friedrich Hermann Löper

Intrinsic amorphous silicon provides excellent surface passivation on crystalline silicon. It has previously been shown, that carriers that are photo generated in the amorphous silicon can be efficiently electronically injected into the crystalline silicon ...

IEEE2018

Recombination Analysis of Phosphorus-Doped Nanostructured Silicon Oxide Passivating Electron Contacts for Silicon Solar Cells

Christophe Ballif, Franz-Josef Haug, Andrea Ingenito, Matthieu Despeisse, Gizem Nogay, Philipp Friedrich Hermann Löper, Philippe Wyss, Josua Andreas Stückelberger

2018

Charge carrier transport mechanisms of passivating contacts studied by temperature-dependent J-V measurements

Gizem Nogay, Philipp Friedrich Hermann Löper

2018

Hole-Collection Mechanism in Passivating Metal-Oxide Contacts on Si Solar Cells: Insights From Numerical Simulations

Christophe Ballif, Stefaan De Wolf, Philipp Friedrich Hermann Löper, Stephanie Essig

2018