The Intermediate Band Solar Cell: Progress Toward the Realization of an Attractive Concept

Surface-plasmon enhanced absorption in organic solar cells by employing a periodically corrugated metallic electrode Appl. Phys. Lett. 101, 163303 (2012) Surface-plasmon enhanced absorption in organic solar cells by employing a periodically corrugated metallic electrode APL: Org. Electron. Photonics 5, 234 (2012) Development of pulsed laser deposition for CdS/CdTe thin film solar cells Appl. Phys. Lett. 101, 153903 (2012) Technology-compatible hot carrier solar cell with energy selective hot carrier absorber and carrier-selective contacts Appl. Phys. Lett. 101, 153901 (2012) Additional information on J. Appl. Phys. In this paper, a model for intermediate band solar cells is built based on the generally understood physical concepts ruling semiconductor device operation, with special emphasis on the behavior at low temperature. The model is compared to J L -V OC measurements at concentrations up to about 1000 suns and at temperatures down to 20 K, as well as measurements of the radiative recombination obtained from electroluminescence. The agreement is reasonable. It is found that the main reason for the reduction of open circuit voltage is an operational reduction of the bandgap, but this effect disappears at high concentrations or at low temperatures.

Section: Discussionmentioning

confidence: 99%

Understanding the operation of quantum dot intermediate band solar cells

Ĺuque

Linares

Antolín

et al. 2012

“…[3][4][5] To achieve the overlap, solute concentrations well beyond the equilibrium solubility limits of most solutes in Si must be achieved. 2,6,7 When nanosecond-scale pulsed laser melting (PLM) is applied to ion-implanted Si, the ultra-fast resolidification that follows melting can produce single crystalline Si supersaturated with the implanted solute. To achieve supersaturation, the solidification speed v must be high enough, compared to the diffusive speed v D of the solute, for deviations from local interfacial equilibrium to cause significant solute trapping.…”

Section: Introductionmentioning

confidence: 99%

Supersaturating silicon with transition metals by ion implantation and pulsed laser melting

Recht¹,

Smith²,

Charnvanichborikarn³

et al. 2013

We investigate the possibility of creating an intermediate band semiconductor by supersaturating Si with a range of transition metals (Au, Co, Cr, Cu, Fe, Pd, Pt, W, and Zn) using ion implantation followed by pulsed laser melting (PLM). Structural characterization shows evidence of either surface segregation or cellular breakdown in all transition metals investigated, preventing the formation of high supersaturations. However, concentration-depth profiling reveals that regions of Si supersaturated with Au and Zn are formed below the regions of cellular breakdown.

“…The properties associated to this IB could drastically differ from the properties of the localized deep levels, and in particular, it has been pointed out that the Shockley-Read-Hall (SRH) recombination might be reduced once the IB is formed. 8 The formation of Si supersaturated materials seems to have been accomplished by means of ion implantation followed by pulsed laser melting (PLM), 9 producing recently remarkable results. 10,11 Ion implantation permits to lodge a non-equilibrium concentration of deep impurities in a superficial layer but the lattice is severely damaged during the process.…”

Section: Introductionmentioning

confidence: 99%

Ruling out the impact of defects on the below band gap photoconductivity of Ti supersaturated Si

Olea

Pastor

Prado

et al. 2013

In this study, we present a structural and optoelectronic characterization of high dose Ti implanted Si subsequently pulsed-laser melted (Ti supersaturated Si). Time-of-flight secondary ion mass spectrometry analysis reveals that the theoretical Mott limit has been surpassed after the laser process and transmission electron microscopy images show a good lattice reconstruction. Optical characterization shows strong sub-band gap absorption related to the high Ti concentration. Photoconductivity measurements show that Ti supersaturated Si presents spectral response orders of magnitude higher than unimplanted Si at energies below the band gap. We conclude that the observed below band gap photoconductivity cannot be attributed to structural defects produced by the fabrication processes and suggest that both absorption coefficient of the new material and lifetime of photoexcited carriers have been enhanced due to the presence of a high Ti concentration. This remarkable result proves that Ti supersaturated Si is a promising material for both infrared detectors and high efficiency photovoltaic devices. V C 2013 AIP Publishing LLC.