III-Nitrides on Silicon Photovoltaics by Sputtering
Mentor: Sirona Valdueza Felip
Email: sirona.valduezafelip@uah.es
Phone: (+34) 918826908-2
University: Universidad de Alcalá
Partner Host Institution: N.A
Keywords: III-nitride semiconductors, AlInN and InGaN alloys, silicon, heterojunction, sputtering, solar cells, low cost

III-Nitrides on Silicon Photovoltaics by Sputtering

This research line aims to establish a technology platform for the fabrication of a new generation of low-cost photovoltaic cells based on nanostructured III-nitride layers synthesized by radio frequency sputtering on silicon substrates. Currently, the photovoltaic market is dominated by single-junction crystalline Si modules because of their relatively low costs and their long-term reliability. Higher conversion efficiencies are obtained using GaAs multi-junction cells operating under concentration light. However, these cells present problems of toxicity. This research line aims to develop a major break-through in the solar domain with fully hybrid III-nitride-on-Si photovoltaic devices environmentally friendly, low production costly, and with moderate conversion efficiencies. The scalability in substrate size and flexibility of available source materials render radio frequency sputtering appropriate for the thin-film photovoltaic industry. Furthermore, the outstanding physical and chemical stability of III-nitrides enables them to operate in harsh environments, showing high stability under concentration conditions and superior resistance to high-energy particle radiation. These new solar cells contain high-In content 2D layers and nanocolumns of AlInN or InGaN directly on silicon. The research line faces a number of technological challenges related to the adaptation of the design, the growth and the fabrication technology of the devices to the specifities of ternary alloys deposited by radio frequency sputtering. Three novel approaches are incorporated into the solar cells: (i) growth of high In-content nanocolumns on silicon, to increase light trapping never attempted so far with radio frequency sputtering, and (ii) texturization of planar solar cells by nanostructuring its surface to reduce the losses caused by light reflection, (iii) incorporation of layers with a gradient in alloy content to move towards full-solar spectrum photovoltaics. This research line is within the line of the Spanish strategy for science, technology and innovation, and the Horizon 2020 program of the European Union: safe, clean and efficient energy.

Departament: Electronics
Research Group: Photonic Engineering Group
More Information: https://grifo.depeca.uah.es/
Relevants projects on the area: AlInN depositado por pulverización catódica para hetero-unIones con Silicio (ANIS). Ref.: CCG2018/EXP-042. Programa propio de la Universidad de Alcalá. Fechas: 01/01/2019-31/12/2019. Dotación: 9k€
Relevants publications on the area: 1.- "In rich AlxIn1˗xN grown by RF sputtering on sapphire: from closely-packed columnar to high surface quality compact layers". A. Núñez Cascajero; S. Valdueza Felip; L. Monteagudo Lerma; E. Monroy; E. Taylor; R.W. Martin; M. González-Herráez; F.B. Naranjo. J. Phys. D: Appl. Phys. 50 065101 (2017)
2.- "Influence of the AlN interlayer thickness on the photovoltaic properties of in-rich AlInN on Si heterojunctions deposited by RF sputtering". S. Valdueza-Felip, A. Núñez-Cascajero, R. Blasco, D. Montero, L. Grenet, M. de la Mata, S. Fernández, L. Rodríguez-De Marcos, J. A. Méndez, S. I. Molina, J. Olea, F. B. Naranjo. AIP Advances 8, 115315 (2018)