III-V nanowires (NWs) have recently emerged as a promising candidate for the direct growth of perfect III-V crystals on silicon, and open new perspectives for the conception and fabrication of tandem solar cells.
Using MBE with the vapor–liquid–solid (VLS) growth mechanism, we have recently tackled several issues within a collaborative framework involving several C2N teams, IPVF, and INL in particular. We made important advances in the growth optimization of regular GaAs/AlGaAs core-shell arrays (M. Vettori et al.), in the precise control of GaAsP alloys to reach the optimal bandgap for III-V/Si tandem solar cells (R. de Lépinau et al., C. Himwas et al.), and in the growth of thin wide-bandgap shells for passivation (R. de Lépinau et al., C. Himwas et al.). Structural and optical properties of nanowires have been investigated by scanning transmission electron microscopy (STEM) and EDX spectroscopy, together with cathodoluminescence mapping of single nanowires.
The results published in several articles this year (see below) constitute a key step in the realization of III-V nanowire solar cells made of core-shell heterostructures. First devices have been successfully fabricated and characterized… stay tuned!
- Evidence and control of unintentional As-rich shells in GaAs1–xPx nanowires, Romaric de Lépinau, Andrea Scaccabarozzi, Gilles Patriarche, Laurent Travers, Stéphane Collin, Andrea Cattoni, Fabrice Oehler, Nanotechnology 30, 294003, 2019.
- Correlated optical and structural analyses of individual GaAsP/GaP core–shell nanowires, C. Himwas, S. Collin, H.-L. Chen, G. Patriarche, F. Oehler, L. Travers, O. Saket, F. H. Julien, J.-C. Harmand, M. Tchernycheva, Nanotechnology 30, 304001, 2019.
- Investigation of GaN nanowires containing AlN/GaN multiple quantum discs by EBIC and CL techniques, Valerio Piazza, Andrey V. Babichev, Lorenzo Mancini, Martina Morassi, Patrick Quach, Fabien Bayle, Ludovic Largeau, François H. Julien, Pierre Rale, Stéphane Collin, Jean-Christophe Harmand, Noelle Gogneau, Maria Tchernycheva, Nanotechnology 30, 214006, 2019.
- Growth optimization and characterization of regular arrays of GaAs/AlGaAs core/shell nanowires for tandem solar cells on silicon, Marco Vettori, Valerio Piazza, Andrea Cattoni, Andrea Scaccabarozzi, Gilles Patriarche, Philippe Regreny, Nicolas Chauvin, Claude Botella, Genevieve Grenet, Jose Penuelas, Alain Fave, Maria Tchernycheva, Michel Gendry, Nanotechnology 30, 084005, 2019.
- In-situ passivation of GaAsP nanowires, C. Himwas, S. Collin, P. Rale, N. Chauvin, G. Patriarche, F. Oehler, F. H. Julien, L. Travers, J.-C. Harmand, M. Tchernycheva, Nanotechnology 28, 495707, 2017.