Aïcha Hessler-Wyser

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The usefulness of Transmission Electron Microscopy (TEM) for the fabrication of high-performance textured amorphous/crystalline silicon (a-Si:H/c-Si) heterojunction (HJ) solar cells is demonstrated. The classical characterization techniques used to monitor the a-Si:H layers properties incorporated into flat HJ solar cells with high open-circuit voltages up to VOC=710 mV and electrical conversion efficiencies up to

This work addresses the need for precise control of thin film sputtering processes to enable thin film material tailoring on the example of zinc tin nitride (ZTN) thin films deposited via microwave plasma-assisted high power reactive magnetron sputtering ( ...

The stability of Nd-nickelate, considered as an alternative solid oxide fuel cell (SOFC) cathode material, was evaluated in this work on its tolerance towards contaminants. ...

Carrier recombination at the metal-semiconductor contacts has become a significant obstacle to the further advancement of high-efficiency diffused-junction silicon solar cells. This paper provides the proof-of-concept of a procedure to reduce contact recom ...

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 ...

Solid oxide fuel cells are able to convert fuels, including hydrocarbons, to electricity with an unbeatable efficiency even for small systems. One of the main limitations for long-term utilization is the reduction-oxidation cycling (RedOx cycles) of the ni ...

The common technology for solid oxide fuel cells (SOFC) is based on a cermet anode of nickel with yttrium stabilized zirconia (YSZ), often used as the supporting structure. One of the main limitations of this anode technology is the redox tolerance. In thi ...

This work focuses on the low temperature fabrication process of InN thin films via microwave plasma-assisted reactive high power impulse magnetron sputtering (MAR-HiPIMS). The influence of microwave plasma on the HiPIMS discharge process at various nitroge ...

The defects located at surface and grain boundaries are generally agreed to be the key factors limiting the power conversion efficiency and operational stability of the halide perovskite solar cells. Therefore, new techniques for surface and grain boundaries passivation are being continuously developed and studied. In this work, we investigate the impact of diffuse coplanar surface barrier discharge (DCSBD) nitrogen plasma treatment on the photoluminescence properties and performance of halide perovskite th

Flexible large-area organic light-emitting diodes (OLEDs) require highly conductive and transparent anodes for efficient and uniform light emission. Tin-doped indium oxide (ITO) is the standard anode in industry. However, due to the scarcity of indium, alt ...

When AxGa1-xAs layers are grown on V-grooved GaAs substrates by metal organic chemical vapour deposition (MOCVD), a Ga rich vertical quantum well (VQW) appears in the V-groove centre. The width and Ga enrichment of this structure depend on the nominal Al concentration and growth temperature. From EELS linescans and spectrum images, concentration profiles and maps of VQWs are obtained, and a subsequent bandstructure calculation shows up to three confined sublevels in the VQW. Carrier confinement in segments

Solid Oxide Fuel Cells (SOFC) are an efficient energy technology for converting different types of fuels to electricity and heat. An important material limitation, especially for (planar) Ni-based anode supported cells, is their redox stability. The nickel volume change between its metallic and oxide state is destroying the thin electrolyte. Thereby it is crucial to understand mechanisms of nickel reduction, oxidation and coarsening in this system. Reduction parameters are also important from an electrochem

The biomedical industry has an increasing demand for processes to join dissimilar metals, such as laser welding of NiTi and stainless steel wires. A region of the weld close to the NiTi interface, which previously was shown to be prone to cracking, was fur ...

This work aimed to set new guidelines for the quantification of Cr accumulation in solid oxide fuel cell cathodes after operation, and enabled to pinpoint a diffusion-controlled tolerance to Cr-poisoning for increased cathode thickness; the additional cath ...

We investigate the structural evolution of polycrystalline zinc oxide films grown by low pressure metal-organic chemical vapor deposition. The goal is to achieve larger grains-leading to higher charge carrier mobility from lower grain boundary density-by c ...

Zinc and tin oxides are both earth-abundant materials with demonstrated applicability as electrodes in several optoelectronic devices. The presence of grain boundaries in these polycrystalline films generally limits the electron mobility. By a combinatoria ...

Substituting the doped amorphous silicon films at the front of silicon heterojunction solar cells with wide-bandgap transition metal oxides can mitigate parasitic light absorption losses. This was recently proven by replacing p-type amorphous silicon with ...

The detection and quantification of small quantities of Cr in (La,Sr)MnO3/Y–ZrO2 solid oxide fuel cell (SOFC) cathodes by energy-dispersive X-ray spectroscopy (EDXS) is not straightforward as Cr X-ray emission lines overlap with La/Mn and O lines. This wor ...

This paper reports on the fabrication of In xGa 1 - xN (InGaN) layers with various compositions ranging from InN to GaN using a cost-effective low-temperature plasma-enhanced chemical vapor deposition (PECVD) method and analyzes the influence of deposition ...

In this article, we report on the use of transmission electron microscopy (TEM) for the fabrication of high-performance textured amorphous/crystalline silicon (a-Si:H/c-Si) heterojunction (HJ) solar cells. Whereas classical thin-film characterization techn ...

Aïcha Hessler-Wyser

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TEM characterization of textured silicon heterojunction solar cells

Nanostructure and Optical Property Tailoring of Zinc Tin Nitride Thin Films through Phenomenological Decoupling: A Pathway to Enhanced Control

Nd-nickelate solid oxide fuel cell cathode sensitivity to Cr and Si contamination

Amorphous silicon enhanced metal-insulator-semiconductor contacts for silicon solar cells

Strategies for Doped Nanocrystalline Silicon Integration in Silicon Heterojunction Solar Cells

A Review of RedOx Cycling of Solid Oxide Fuel Cells Anode

Redox study of anode supported solid oxide fuel cell

Microwave plasma-assisted reactive HiPIMS of InN films: Plasma environment and material characterisation

Defect Passivation via Plasma Modification of Lead Halide Perovskite Thin Films

An Indium-Free Anode for Large-Area Flexible OLEDs: Defect-Free Transparent Conductive Zinc Tin Oxide

Use of quantitative EELS and cathodoluminescence for study of carrier confinement and diffusion in self organized vertical quantum wells

Reduction and Oxidation Study of Anode Supported Solid Oxide Fuel Cell

Three-dimensional chemical analysis of laser-welded NiTi–stainless steel wires using a dual-beam FIB

Cathode thickness-dependent tolerance to Cr-poisoning in solid oxide fuel cells

Increasing Polycrystalline Zinc Oxide Grain Size by Control of Film Preferential Orientation

High performance amorphous Zn-Sn-O: impact of composition, microstructure, and thermal treatments in the optoelectronic properties

22.5% efficient silicon heterojunction solar cell with molybdenum oxide hole collector

Rapid chromium quantification in solid oxide fuel cell cathodes

Bandgap engineering of indium gallium nitride layers grown by plasma-enhanced chemical vapor deposition

Textured silicon heterojunction solar cells with over 700mV open-circuit voltage studied by transmission electron microscopy