Publications by Franz-Josef Haug

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We fabricated amorphous silicon n-i-p solar cells with two types of nanopatterned back reflectors using stencil lithography. One reflector type has a plasmonic grating that is embedded in the ZnO layer; the other one has a metallic grating patterned on top ...

Recent improvements in light-emitting diode (LED) technology has allowed for the use of LEDs for solar simulators with excellent characteristics. In this paper, we present a solar simulator prototype fully based on LEDs. Our prototype has been designed spe ...

An approach that models the fabrication and enables the characterization of randomly self-textured silicon thin film solar cells is developed and are compared to experimental results. The optical and electrical properties of the solar cells depend on the m ...

We determine the limiting efficiency for monolithic tandem solar cells that employ crystalline silicon for the top-cell as well as for the bottom cell. In such a design, the top-cell extends over the region of very high generation rate that forms at the fr ...

An amorphous silicon solar cell on a periodic nanocone back reflector with a high 9.7% initial conversion efficiency is presented. The optimized back-reflector morphology provides powerful light trapping and enables excellent electrical cell performance. U ...

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 ...

Polysilicon recombination junctions whose n-type bottom layers double as a passivating contact to the silicon surface are investigated. Such recombination junctions are a key element in the interconnection of tandem devices with a silicon bottom cell, and ...

In this contribution, the replication of nano-textures enhancing the short circuit current of thin film silicon solar cells onto low cost substrates (glass or PolyEthylene Naphtalate (PEN)) is studied. Optical and morphological analysis is performed to ass ...

Implementing antireflection (AR) coatings in micromorph tandem solar cells is a challenging process in which not only more sunlight should get conducted into the cells, but also the current matching between subcells should either be maintained or get impro ...

We investigate the influence of the oxygen content in boron-doped nanocrystalline silicon oxide films (p-nc-SiOx) and introduce this material as window layer in n-i-p solar cells. The dependence of both, optical and electrical properties on the oxygen cont ...

Hydrogenated amorphous silicon (alpha-Si:H) has been used for decades doped and as intrinsic absorber layers in thin-film silicon solar cells. Whereas their effiency was improved for a long time by the deposition of higher quality absorber layers, recent i ...

High-efficiency thin-film silicon triple-junction solar cells in p-i-n configuration have been fabricated using amorphous silicon top cell absorber layers, as well as microcrystalline silicon middle and bottom cell absorbers. The triple-junction cells were ...

Replacing silver metallization with earth-abundant materials in Si solar cells is a critical step towards the sustainable growth of photovoltaics. In this work, we investigate fire-through processes using Al for the metallization of solar cells with p-type ...

Surface textures in thin-film silicon multi-junction solar cells play an important role in gaining the photocurrent of the devices. In this paper, a design of the textures is carried out for the case of amorphous silicon/micro-crystalline silicon (a-Si:H/m ...

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 ...

Thin-film Si solar cells employ a back reflector (BR) for a more efficient use of the long wavelength light. Here, we have carried out a cross evaluation of metal (Ag-based) and dielectric (white paint-based) BR designs. Conclusive results have been reache ...

Passivating contacts are indispensable for achieving high conversion efficiency in crystalline-silicon solar cells. Their realization and integration into a convenient process flow have become crucial research objectives. Here, we report an alternative pas ...

We propose an autonomous battery-less wireless sensor node that combines on a single printed circuit board an ultra-wideband (UWB) transmitter and its printed antenna, together with a piezoelectric cantilever and a solar cell array to harvest vibrations an ...

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 ...

Franz-Josef Haug

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Stencil-nanopatterned back reflectors for thin-film amorphous silicon n-i-p solar cells

Class AAA LED-Based Solar Simulator for Steady-State Measurements and Light Soaking

From randomly self-textured substrates to highly efficient thin film solar cells: Influence of geometric interface engineering on light trapping, plasmonic losses and charge extraction

A recalculation of the efficiency limit in crystalline Si/Si tandem solar cells

High-Efficiency Amorphous Silicon Solar Cell on a Periodic Nanocone Back Reflector

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

Passivating Polysilicon Recombination Junctions for Crystalline Silicon Solar Cells

NANO-IMPRINT TECHNIQUE FOR BACK REFLECTOR IN HIGH EFFICIENCY N-I-P THIN FILM SILICON SOLAR CELLS

Simultaneous realization of light distribution and trapping in micromorph tandem solar cells using novel double-layered antireflection coatings

Window layer with p doped silicon oxide for high V-oc thin-film silicon n-i-p solar cells

Review: Progress in solar cells from hydrogenated amorphous silicon

Thin-Film Silicon Triple-Junction Solar Cells on Highly Transparent Front Electrodes With Stabilized Efficiencies up to 12.8%

Interactions between aluminium and fired passivating contacts during fire-through metallization

Design of periodic nano- and macro-scale textures for high-performance thin-film multi-junction solar cells

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

Metal versus dielectric back reflector for thin-film Si solar cells with impact of front electrode surface texture

Stencil-Nanopatterned Back Reflectors for Thin-Film Amorphous Silicon n-i-p Solar Cells

A passivating contact for silicon solar cells formed during a single firing thermal annealing

A low-cost UWB sensor node powered by a piezoelectric harvester or solar cells

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