Publications de Sonia Conesa Boj

Towards higher electron mobility in modulation doped GaAs/AlGaAs core shell nanowires

Anna Fontcuberta i Morral, Gözde Tütüncüoglu, Sonia Conesa Boj

Precise control over the electrical conductivity of semiconductor nanowires is a crucial prerequisite for implementation of these nanostructures into novel electronic and optoelectronic devices. Advances in our understanding of doping mechanisms in nanowir ...

Royal Society of Chemistry2017

Synthesis, Morphological, and Electro-optical Characterizations of Metal/Semiconductor Nanowire Heterostructures

Anna Fontcuberta i Morral, Sonia Conesa Boj, Heidi Andrea Potts

In this letter, we demonstrate the formation of unique Ga/GaAs/Si nanowire heterostructures, which were successfully implemented in nanoscale light-emitting devices with visible room temperature electroluminescence. Based on our recent approach for the int ...

American Chemical Society2016

Modulation Doping of GaAs/AlGaAs Core-Shell Nanowires With Effective Defect Passivation and High Electron Mobility

Anna Fontcuberta i Morral, Sonia Conesa Boj, Alberto Casadei, Federico Matteini, Fauzia Jabeen, Francesca Amaduzzi

Reliable doping is required to realize many devices based on semiconductor nanowires. Group IIIV nanowires show great promise as elements of high-speed optoelectronic devices, but for such applications it is important that the electron mobility is not comp ...

American Chemical Society2015

High Yield of GaAs Nanowire Arrays on Si Mediated by the Pinning and Contact Angle of Ga

Anna Fontcuberta i Morral, Anna Dalmau Mallorquí, Gözde Tütüncüoglu, Sonia Conesa Boj, Eleonora Russo, Federico Matteini, Jelena Vukajlovic Plestina, Heidi Andrea Potts

GaAs nanowire arrays on Silicon offer great perspectives in the :optoeleetronics and solar cell industry. To fulfill this potential, gold-free growth in predetermined positions should be achieved. Ga-assisted growth of GaAs nano-wires in the form of array ...

American Chemical Society2015

Terahertz spectroscopy of modulation doped core-shell GaAs/AlGaAs nanowires

Anna Fontcuberta i Morral, Daniel Rüffer, Sonia Conesa Boj, Alberto Casadei, Federico Matteini, Francesca Amaduzzi

In order to realize many devices based on semiconductor nanowires, reliable doping is essential. For such devices, it is important that the electron mobility is not compromised by doping incorporation. Here, we show that core-shell GaAs/AlGaAs nanowires ca ...

IEEE2015

Bottom-up engineering of InAs at the nanoscale: From V-shaped nanomembranes to nanowires

Anna Fontcuberta i Morral, Anna Dalmau Mallorquí, Gözde Tütüncüoglu, Sonia Conesa Boj, Eleonora Russo, Ignasi Canales Mundet

The ability to rationally tune the morphology of nanostructures is a fundamental milestone in nanoscale engineering. In particular, the possibility to switch between different shapes within the same material system represents a further step in the developm ...

Elsevier2015

Cracking the Si Shell Growth in Hexagonal GaP-Si Core-Shell Nanowires

Anna Fontcuberta i Morral, Sonia Conesa Boj

Semiconductor nanowires have increased the palette of possible heterostructures thanks to their more effective strain relaxation. Among these core shell heterostructures are much more sensitive to strain than axial Ones. It is now accepted that the formati ...

American Chemical Society2015

Analysis of the Atomic Layer Deposited Al2O3 field-effect passivation in black silicon

Anna Fontcuberta i Morral, Sonia Conesa Boj

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 that the low surface recombination velocity results from a higher sensi ...

Elsevier2015

Quantum dots in the GaAs/AlxGa1-xAs core-shell nanowires: Statistical occurrence as a function of the shell thickness

Yannik Fontana, Anna Fontcuberta i Morral, Gözde Tütüncüoglu, Léo Duchêne, Sonia Conesa Boj, Federico Matteini, Luca Francaviglia

Quantum dots (QDs) embedded in nanowires represent one of the most promising technologies for applications in quantum photonics. Self-assembled bottom-up fabrication is attractive to overcome the technological challenges involved in a top-down approach, bu ...

American Institute of Physics2015

Plastic and Elastic Strain Fields in GaAs/Si Core-Shell Nanowires

Christophe Ballif, Anna Fontcuberta i Morral, Martin Heiss, Sylvain Dunand, Sonia Conesa Boj, Eleonora Russo

Thanks to their unique morphology, nanowires have enabled integration of materials in a way that was not possible before with thin film technology. In turn, this opens new avenues for applications in the areas of energy harvesting, electronics, and optoele ...

American Chemical Society2014

Gold-Free Ternary III-V Antimonide Nanowire Arrays on Silicon: Twin-Free down to the First Bilayer

Anna Fontcuberta i Morral, Sonia Conesa Boj

With the continued maturation of III-V nanowire research, expectations of material quality should be concomitantly raised. Ideally, III-V nanowires integrated on silicon should be entirely free of extended planar defects such as twins, stacking faults, or ...

American Chemical Society2014

Probing inhomogeneous composition in core/shell nanowires by Raman spectroscopy

Anna Fontcuberta i Morral, Martin Heiss, Gözde Tütüncüoglu, Sonia Conesa Boj, Esther Alarcon Llado, Eleonora Russo, Federico Matteini, Francesca Amaduzzi

Due to its non-destructive and its micro-spatial resolution, Raman spectroscopy is a powerful tool for a rapid structural and compositional characterization of nanoscale materials. Here, by combining the compositional dependence of the Raman peaks with the ...

American Institute of Physics2014

Three-dimensional nanoscale study of Al segregation and quantum dot formation in GaAs/AlGaAs core-shell nanowires

Yannik Fontana, Anna Fontcuberta i Morral, Martin Heiss, Sonia Conesa Boj, Eleonora Russo, Luca Francaviglia

GaAs/Al-GaAs core-shell nanowires fabricated by molecular beam epitaxy contain quantum confining structures susceptible of producing narrow photoluminescence (PL) and single photons. The nanoscale chemical mapping of these structures is analyzed in 3D by a ...

American Institute of Physics2014

III-V nanowire arrays: growth and light interaction

Anna Fontcuberta i Morral, Martin Heiss, Anna Dalmau Mallorquí, Gözde Tütüncüoglu, Sonia Conesa Boj, Esther Alarcon Llado, Eleonora Russo, Federico Matteini

Semiconductor nanowire arrays are reproducible and rational platforms for the realization of high performing designs of light emitting diodes and photovoltaic devices. In this paper we present an overview of the growth challenges of III-V nanowire arrays o ...

Institute of Physics2014

Hybrid axial and radial Si-GaAs heterostructures in nanowires

Christophe Ballif, Anna Fontcuberta i Morral, Martin Heiss, Sylvain Dunand, Daniel Rüffer, Sonia Conesa Boj, Eleonora Russo

Hybrid structures are formed from materials of different families. Traditionally, group IV and III-V semiconductors have not been integrated together in the same device or application. In this work we present a new approach for obtaining Si-GaAs hybrid het ...

Royal Society of Chemistry2013

Three-Dimensional Magneto-Photoluminescence as a Probe of the Electronic Properties of Crystal-Phase Quantum Disks in GaAs Nanowires

Pierre Michel Corfdir, Anna Fontcuberta i Morral, Emanuele Uccelli, Sonia Conesa Boj

Crystal-phase engineering has emerged as a novel method of bandgap engineering, made feasible by the high surface-to-volume ratio of nanowires. There remains intense debate about the exact characteristics of the band structure of the novel crystal phases, ...

Amer Chemical Soc2013

Self-assembled quantum dots in a nanowire system for quantum photonics

Marco Cantoni, Yannik Fontana, Anna Fontcuberta i Morral, Martin Heiss, Bernt Ketterer, Sonia Conesa Boj, Eleonora Russo, Nicola Marzari

Quantum dots embedded within nanowires represent one of the most promising technologies for applications in quantum photonics. Whereas the top-down fabrication of such structures remains a technological challenge, their bottom-up fabrication through self-a ...

Nature Publishing Group2013

Exciton localization mechanisms in wurtzite/zinc-blende GaAs nanowires

Anna Fontcuberta i Morral, Martin Heiss, Emanuele Uccelli, Sonia Conesa Boj

We investigate the emission properties of excitons in GaAs nanowires containing quantum disks formed by structural alternation between the zinc-blende and wurtzite phases, by means of temperature-dependent photoluminescence. At 10 K the emission from an en ...

American Physical Society (APS)2013

Growth mechanisms and process window for InAs V-shaped nanoscale membranes on Si[001]

Anna Fontcuberta i Morral, Martin Heiss, Anna Dalmau Mallorquí, Gözde Tütüncüoglu, Sonia Conesa Boj, Esther Alarcon Llado, Eleonora Russo, Ignasi Canales Mundet

Organized growth of high aspect-ratio nanostructures such as membranes is interesting for opto-electronic and energy harvesting applications. Recently, we reported a new form of InAs nano-membranes grown on Si substrates with enhanced light scattering prop ...

Institute of Physics2013

Raman spectroscopy of self-catalyzed GaAs1-xSbx nanowires grown on silicon

Anna Fontcuberta i Morral, Sonia Conesa Boj, Esther Alarcon Llado

Thanks to their wide band structure tunability, GaAs1-xSbx nanowires provide exciting perspectives in optoelectronic and energy harvesting applications. The control of composition and strain of these ternary alloys is crucial in the determination of their ...

Institute of Physics2013