Superior radiation resistance of In1−xGaxN alloys: Full-solar-spectrum photovoltaic material system

Wu, Junqiao; Walukiewicz, W.; Yu, K. M.; Shan, W.; Ager, Joel W.; Haller, E. E.; Lu, Hai; Schaff, William J.; Metzger, Wyatt K.; Kurtz, Sarah

doi:10.1063/1.1618353

Cited by 596 publications

(313 citation statements)

References 28 publications

Supporting

Mentioning

310

Contrasting

Order By: Relevance

“…These properties include the ability to tune the bandgap of InGaN across nearly the entire solar spectrum (0.7eV-3.4eV) [2], high absorption coefficient (~10 5 cm -1 ) [3], and high radiation resistance [4]. In theory these properties, could translate into solar cells with high efficiency, in thin layers, and with long lifetimes.…”

Section: Introductionmentioning

confidence: 99%

III-nitride core–shell nanowire arrayed solar cells

Wierer

Li²,

Koleske³

et al. 2012

Nanotechnology

View full text Add to dashboard Cite

A solar cell based on a III-nitride hybrid nanowire-film architecture is demonstrated. It consists of a vertically-aligned array of InGaN/GaN multi-quantum well core-shell nanowires, electrically connected by a coalesced p-type InGaN canopy layer. This hybrid structure allows for standard planar device processing, solving an important challenge with nanowire device integration. It also enables various advantages such as higher indium composition InGaN layers via elastic strain relief, efficient carrier collection through thin layers, and enhanced light trapping. This proof-of-concept nanowire-based device presents a path forward for highefficiency III-nitride solar cells. Fabricated III-nitride nanowire solar cells exhibit a photoresponse out to 2.1eV and short circuit current density of ~1 mA/cm 2 (1 sun AM1.5G). 4 ACKNOWLEDGMENTS5

show abstract

Section: Introductionmentioning

confidence: 99%

III-nitride core–shell nanowire arrayed solar cells

Wierer

Li²,

Koleske³

et al. 2012

Nanotechnology

View full text Add to dashboard Cite

show abstract

“…However, indium is a relatively scarce, and consequently expensive, element, which is desired not only for TCOs, but also, for example, as an active component in the rapidly expanding range of InGaN-based optoelectronic, electronic and photovoltaic devices [9][10][11][12][13]. Consequently, much recent work has been focussed on alternative materials [14].…”

Section: Introductionmentioning

confidence: 99%

Conductivity in transparent oxide semiconductors

King

Veal

2011

J. Phys.: Condens. Matter

225

180

View full text Add to dashboard Cite

Abstract. Despite an extensive research effort for over 60 years, an understanding of the origins of conductivity in wide band-gap transparent conducting oxide (TCO) semiconductors remains elusive. While TCOs have already found widespread use in device applications requiring a transparent contact, there are currently enormous efforts to (i) increase the conductivity of existing materials, (ii) identify suitable alternatives, and (iii) attempt to gain semiconductor-engineering levels of control over their carrier density, essential for the incorporation of TCOs into a new generation of multifunctional transparent electronic devices. These efforts, however, are dependent on a microscopic identification of the defects and impurities leading to the high unintentional carrier densities present in these materials. Here, we review recent developments towards such an understanding. While oxygen vacancies are commonly assumed to be the source of the conductivity, there is increasing evidence that this is not a sufficient mechanism to explain the total measured carrier concentrations. In fact, many studies suggest that oxygen vacancies are deep, rather than shallow, donors, and their abundance in as-grown material is also debated. We discuss other potential contributions to the conductivity in TCOs, including other native defects, their complexes, and in particular hydrogen impurities. Convincing theoretical and experimental evidence is presented for the donor nature of hydrogen across a range of TCO materials, and while its stability and the presence of interstitial and substitutional species are still somewhat open questions, it is one of the leading contenders for unintentional conductivity in TCOs. We also review recent work indicating that the surfaces of TCOs can support very high carrier densities, opposite to the case of conventional semiconductors. In thin-film materials/devices and, in particular, nanostructures, the surface can have a large impact on the total conductivity in TCOs. We discuss models that attempt to explain both the bulk and surface conductivity based on features of the bulk band structure common across the TCOs, and compare these materials to other semiconductors. Finally, we briefly consider transparency in these materials, and its interplay with conductivity. Understanding this interplay, as well as the microscopic contenders for the conductivity of these materials, will prove essential to the future design and control of TCO semiconductors, and their implementation into novel multifunctional devices.

show abstract

“…1 Their unique and intriguing merits include continuously tunable wide band gap from 0.70 eV to 3.4 eV, strong absorption coefficient on the order of 10 5 cm À1 , superior radiation resistance under harsh environment, and high saturation velocities and high mobility. 2 Calculation from the detailed balance model also revealed that in multi-junction (MJ) solar cell device, materials with band gaps higher than 2.4 eV are required to achieve PV efficiencies greater than 50%, 3 which is practically and easily feasible for InGaN materials. Other state-of-art modeling on InGaN solar cells also demonstrate great potential for applications of III-nitride solar cells in four-junction solar cell devices as well as in the integration with a non-III-nitride junction in multi-junction devices.…”

Section: Introductionmentioning

confidence: 99%