R. Alcubilla

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This paper describes a fabrication process to obtain high efficiency c-Si cells (> 20%) based on the Laser Fired Contact Passivated Emitter Rear Cell (LFC-PERC) concept. Photovoltaic efficiencies beyond 20% have been achieved using thermal SiO2 as a rear passivation layer on 2 cm x 2 cm solar cells with 0.45 cm Fz c-Si substrates. Efficiencies up to 22%(More)
The electrophysiological characterisation of cultured neurons is of paramount importance for drug discovery, safety pharmacology and basic research in the neurosciences. Technologies offering low cost, low technical complexity and potential for scalability towards high-throughput electrophysiology on in vitro neurons would be advantageous, in particular for(More)
The nanostructuring of silicon surfaces--known as black silicon--is a promising approach to eliminate front-surface reflection in photovoltaic devices without the need for a conventional antireflection coating. This might lead to both an increase in efficiency and a reduction in the manufacturing costs of solar cells. However, all previous attempts to(More)
Selective thermal emitters concentrate most of their spontaneous emission in a spectral band much narrower than a blackbody. When used in a thermophovoltaic energy conversion system, they become key elements defining both its overall system efficiency and output power. Selective emitters' radiation spectra must be designed to match their accompanying(More)
Pentacene thin-film transistors have been obtained using polymethyl methacrylate as a gate dielectric. The maximum process temperature was 170 C, which corresponds to the baking of the polymeric gate dielectric. These devices presented good electrical performances with field-effect mobilities of 0.01 cm V 1 s 1 and low threshold voltages ()15 V). Atomic(More)
x.doi.org/10.1016/j.solmat.2015.05.027 48/& 2015 Elsevier B.V. All rights reserved. esponding author. Tel.: þ358 504316367. ail address: guillaume.von.gastrow@aalto.fi (G We demonstrate that n-type black silicon can be passivated efficiently using Atomic Layer Deposited (ALD) Al2O3, reaching maximum surface recombination velocities below 7 cm/s. We show(More)
Silicon is the material of choice for visible light photodetection and solar cell fabrication. However, due to the intrinsic band gap properties of silicon, most infrared photons are energetically useless. Here, we show the first example of a photodiode developed on a micrometre scale sphere made of polycrystalline silicon whose photocurrent shows the Mie(More)
Laser-fired contact (LFC) processes have emerged as 5 a promising approach to create rear local electric contacts in p-type 6 crystalline silicon solar cells. Despite this approach has been suc7 cessfully applied in devices showing efficiencies above 20%, there 8 is still a lack of knowledge about some specific features of LFCs 9 at the submicron level. In(More)
The aim of this work is to study the surface passivation of aluminum oxide/amorphous silicon carbide (Al2O3/a-SiCx) stacks on both p-type and n-type crystalline silicon (c-Si) substrates as well as the optical characterization of these stacks. Al2O3 films of different thicknesses were deposited by thermal atomic layer deposition (ALD) at 200 °C and were(More)
In this Letter we report on the thermal properties of macroporous silicon photonic crystals with the unit cell gradually varied along the pore axis. We show experimentally that arbitrarily large omnidirectional total-reflectance bands can be produced with such structures. We also demonstrate that those bands can be effectively used to reduce thermal(More)