Publications de Thomas Söderström

A New View of Microcrystalline Silicon: The Role of Plasma Processing in Achieving a Dense and Stable Absorber Material for Photovoltaic Applications

Christophe Ballif, Matthieu Despeisse, Grégory Bugnon, Thomas Söderström, Gaetano Parascandolo, Peter Cuony, Jakub Holovsky, Simon Hänni

To further lower production costs and increase conversion efficiency of thin-film silicon solar modules, challenges are the deposition of high-quality microcrystalline silicon (μc-Si:H) at an increased rate and on textured substrates that guarantee efficie ...

2012

LPCVD ZnO-based intermediate reflector for micromorph tandem solar cells

Christophe Ballif, Matthieu Despeisse, Sylvain Nicolay, Grégory Bugnon, Laura Ding, Thomas Söderström

The use of zinc oxide (ZnO) based intermediate reflector (ZIR) in micromorph solar cells using low pressure chemical vapor deposition (LPCVD) was investigated. The influences of deposition temperature and dopant gas concentration on grain size and lateral ...

2011

Microcrystalline silicon solar cells: effect of substrate temperature on cracks and their role in post-oxidation

Christophe Ballif, Thomas Söderström, Martin Python

Microcrystalline silicon (mc-Si:H) cells can reach efficiencies up to typically 10% and are usually incorporated in tandem micromorph devices. When cells are grown on rough substrates, ‘‘cracks’’ can appear in the mc-Si:H layers. Previous works have demons ...

2010

ZnO Transparent conductive oxide for thin film silicon solar cells

Christophe Ballif, Franz-Josef Haug, Matthieu Despeisse, Mathieu Gérard Boccard, Sylvain Nicolay, Grégory Bugnon, Sylvie Faÿ, Andrea Feltrin, Peter Cuony, Thomas Söderström

There is general agreement that the future production of electric energy has to be renewable and sustainable in the long term. Photovoltaic (PV) is booming with more than 7GW produced in 2008 and will therefore play an important role in the future electric ...

Spie-Int Soc Optical Engineering, Po Box 10, Bellingham, Wa 98227-0010 Usa2010

Flexible micromorph tandem a-Si/µc-Si solar cells

Christophe Ballif, Franz-Josef Haug, Vanessa Terrazzoni-Daudrix, Thomas Söderström

The deposition of a stack of amorphous (a-Si:H) and microcrystalline (µc- Si:H) tandem thin film silicon solar cells (micromorph) requires at least twice the time used for a single junction a-Si:H cell. However, micromorph devices have a higher potential e ...

2010

Research and developments in thin film silicon photovoltaics

Christophe Ballif, Franz-Josef Haug, Matthieu Despeisse, Grégory Bugnon, Sylvie Faÿ, Andrea Feltrin, Thomas Söderström, Gaetano Parascandolo, Martin Python

The increasing demand for photovoltaic devices and the associated crystalline silicon feedstock demand scenario have led in the past years to the fast growth of the thin film silicon industry. The high potential for cost reduction and the suitability for b ...

2009

Influence of the ZnO buffer layer on the guided mode structure in Si/ZnO/Ag multilayers

Christophe Ballif, Franz-Josef Haug, Vanessa Terrazzoni-Daudrix, Thomas Söderström

We present a study of the optical mode structure in metal-dielectric multilayer structures that represent amorphous silicon thin film solar cells with metallic back contact. Knowledge of the modal structure represents a first step toward describing absorpt ...

2009

FINAL RESULTS OF THE EUROPEAN PROJECT FLEXCELLENCE ROLL TO ROLL TECHNOLOGY FOR THE PRODUCTION OF HIGH EFFICIENCY LOW COST THIN FILM SOLAR CELLS

Christophe Ballif, Franz-Josef Haug, Vanessa Terrazzoni-Daudrix, Thomas Söderström

This paper reports on the final main results of the Flexcellence project. The project was running for 3 years and its goal was the development of equipments and processes for cost-effective roll-to-roll production of high-efficiency flexible thin-film sili ...

2009

Light trapping effects in thin film silicon solar cells

Christophe Ballif, Franz-Josef Haug, Thomas Söderström

We present advanced light trapping concepts for thin film silicon solar cells. When an amorphous and a microcrystalline absorber layers are combined into a micromorph tandem cell, light trapping becomes a challenge because it should combine the spectral re ...

2009

Development of micromorph tandem soalr cells on flexible low cost plastic substrates

Christophe Ballif, Franz-Josef Haug, Xavier Niquille, Vanessa Terrazzoni-Daudrix, Thomas Söderström, Martin Python

We report on the development of fully flexible microcrystalline and micromorph tandem solar cells directly on low-cost substrates like poly-ethylen-terephtalate (PET) and poly-ethylen-naphtalate (PEN). The cells are deposited in nip or nip/nip configuratio ...

2009