Observatorio de I+D+i UPM

Memorias de investigación
Research Publications in journals:
Experimental verification of intermediate band formation on titanium-implanted silicon
Year:2013
Research Areas
  • Electronic devices,
  • Solar cells
Information
Abstract
Intermediate band formation on silicon layers for solar cell applications was achieved by titanium implantation and laser annealing. A two-layer heterogeneous system, formed by the implanted layer and by the un-implanted substrate, was formed. In this work, we present for the first time electrical characterization results which show that recombination is suppressed when the Ti concentration is high enough to overcome the Mott limit, in agreement with the intermediate band theory. Clear differences have been observed between samples implanted with doses under or over the Mott limit. Samples implanted under the Mott limit have capacitance values much lower than the un-implanted ones as corresponds to a highly doped semiconductor Schottky junction. However, when the Mott limit is surpassed, the samples have much higher capacitance, revealing that the intermediate band is formed. The capacitance increasing is due to the big amount of charge trapped at the intermediate band, even at low temperatures. Ti deep levels have been measured by admittance spectroscopy. These deep levels are located at energies which vary from 0.20 to 0.28?eV below the conduction band for implantation doses in the range 1013-1014 at./cm2. For doses over the Mott limit, the implanted atoms become nonrecombinant. Capacitance voltage transient technique measurements prove that the fabricated devices consist of two-layers, in which the implanted layer and the substrate behave as an n+/n junction.
International
Si
JCR
Si
Title
Journal of Applied Physics
ISBN
0021-8979
Impact factor JCR
2,21
Impact info
Volume
113
Journal number
From page
024104
To page
024110
Month
SIN MES
Ranking
Participants
  • Autor: H. Castán
  • Autor: E. Pérez
  • Autor: H. García
  • Autor: S. Dueñas
  • Autor: L. Bailón
  • Autor: Javier Olea Ariza (UPM)
  • Autor: D Pastor
  • Autor: E. García-Hemme
  • Autor: M. Irigoyen
  • Autor: G. González-Diaz
Research Group, Departaments and Institutes related
  • Creador: Grupo de Investigación: Silicio y Nuevos Conceptos para Células Solares
  • Centro o Instituto I+D+i: Instituto de Energía Solar
S2i 2019 Observatorio de investigación @ UPM con la colaboración del Consejo Social UPM
Cofinanciación del MINECO en el marco del Programa INNCIDE 2011 (OTR-2011-0236)
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