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Memorias de investigación
Ponencias en congresos:
Improving the efficiency of InAs/GaAs quantum dot solar cells by engineering the wetting layer
Año:2019
Áreas de investigación
  • Puntos cuanticos,
  • Nanoelectrónica,
  • Células solares,
  • Epitaxias y crecimientos cristalinos,
  • Técnicas de depósito,
  • Tecnologías a escala nano
Datos
Descripción
InAs/GaAs quantum dot (QD) solar cells have been the subject of intense research during last years, not only as a strategy to overcome the Shockley-Queisser efficiency limit through novel concepts such as intermediate band solar cells, but also as a way to extend the effective bandgap of single or multi-junction (sub)cells to the near infrared. Nevertheless, QD solar cells have up to now hardly outperformed control devices. This is due to several problems, in which the wetting layer (WL) may have a relevant but relatively unexplored role. In this work we investigate the performance of InAs/GaAs QD solar cells with engineered WLs grown by molecular beam epitaxy. First we demonstrate a negative impact of the WL on the carrier extraction efficiency of standard InAs/GaAs QD solar cells. Then we analyze different strategies designed to neutralize the effect of the WL based on either a physical modification of the WL or a modification of its electronic structure. The WL thickness can be reduced by modifying the growth conditions of the GaAs capping layer: high capping rates reduce In-Ga intermixing in the QDs and, therefore, In redistribution from the QDs to the WL. Carrier transport through the WLs can also be improved by electronic coupling of the different QD/WL layers and the creation of mini-bands. Finally, the band structure of the WL can be modified and converted to type-II by adding Sb to the capping layer. We show that some of these strategies result in improvements of conversion efficiency under AM1.5 conditions of up to 125% over standard InAs/GaAs QD solar cells.
Internacional
Si
Nombre congreso
SPIE OPTO 2019 (Nano and Quantum Engineered Photovoltaic Devices)
Tipo de participación
960
Lugar del congreso
San Francisco, Estados Unidos
Revisores
Si
ISBN o ISSN
0000000000000
DOI
Fecha inicio congreso
02/02/2019
Fecha fin congreso
09/02/2019
Desde la página
1
Hasta la página
3
Título de las actas
proceedings
Esta actividad pertenece a memorias de investigación
Participantes
  • Autor: Lazar Stanojevic (UPM)
  • Autor: Alicia Gonzalo Martin (UPM)
  • Autor: Antonio David Utrilla Lomas (UPM)
  • Autor: Daniel F. Reyes (UCA)
  • Autor: Verónica Braza (UCA)
  • Autor: David González (UCA)
  • Autor: David Fuertes (UCA)
  • Autor: Adrian Hierro Cano (UPM)
  • Autor: Jose Maria Ulloa Herrero (UPM)
Grupos de investigación, Departamentos, Centros e Institutos de I+D+i relacionados
  • Creador: Grupo de Investigación: Grupo de Dispositivos Semiconductores del ISOM
  • Departamento: Ciencia de Materiales
  • Centro o Instituto I+D+i: Instituto Universitario de Sistemas Optoelectrónicos y Microtecnología
  • Departamento: Ingeniería Electrónica
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