Nature of the Band Gap of<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:msub><mml:mi>In</mml:mi><mml:mn>2</mml:mn></mml:msub><mml:msub><mml:mi mathvariant="normal">O</mml:mi><mml:mn>3</mml:mn></mml:msub></mml:math>Revealed by First-Principles Calculations and X-Ray Spectroscopy

Walsh, Aron; Silva, Juarez L. F. Da; Wei, Su‐Huai; Körber, Christoph; Klein, Andreas; Piper, Louis F. J.; DeMasi, A.; Smith, Kevin; Panaccione, G.; Torelli, Piero; Payne, David J.; Bourlange, A.; Egdell, R.G.

doi:10.1103/physrevlett.100.167402

Cited by 607 publications

(369 citation statements)

References 29 publications

Supporting

Mentioning

321

Contrasting

Unclassified

Order By: Relevance

“…For direct bandgap semiconductors X = 2 is used, whilst for indirect bandgap semiconductors X = 1/2 is used. Since the nature of the bandgap in In 2 O 3 is still under debate,65, 66, 67 we have here used both approaches. ZnO is known to be a direct bandgap semiconductor68 thus the value of X = 2 was employed.…”

Section: Methodsmentioning

confidence: 99%

High Electron Mobility Thin‐Film Transistors Based on Solution‐Processed Semiconducting Metal Oxide Heterojunctions and Quasi‐Superlattices

et al. 2015

View full text Add to dashboard Cite

High mobility thin‐film transistor technologies that can be implemented using simple and inexpensive fabrication methods are in great demand because of their applicability in a wide range of emerging optoelectronics. Here, a novel concept of thin‐film transistors is reported that exploits the enhanced electron transport properties of low‐dimensional polycrystalline heterojunctions and quasi‐superlattices (QSLs) consisting of alternating layers of In2O3, Ga2O3, and ZnO grown by sequential spin casting of different precursors in air at low temperatures (180–200 °C). Optimized prototype QSL transistors exhibit band‐like transport with electron mobilities approximately a tenfold greater (25–45 cm2 V−1 s−1) than single oxide devices (typically 2–5 cm2 V−1 s−1). Based on temperature‐dependent electron transport and capacitance‐voltage measurements, it is argued that the enhanced performance arises from the presence of quasi 2D electron gas‐like systems formed at the carefully engineered oxide heterointerfaces. The QSL transistor concept proposed here can in principle extend to a range of other oxide material systems and deposition methods (sputtering, atomic layer deposition, spray pyrolysis, roll‐to‐roll, etc.) and can be seen as an extremely promising technology for application in next‐generation large area optoelectronics such as ultrahigh definition optical displays and large‐area microelectronics where high performance is a key requirement.

show abstract

Section: Methodsmentioning

confidence: 99%

High Electron Mobility Thin‐Film Transistors Based on Solution‐Processed Semiconducting Metal Oxide Heterojunctions and Quasi‐Superlattices

et al. 2015

View full text Add to dashboard Cite

show abstract

“…(a) Calculated band structure around the zone centre of In 2 O 3 indicating the allowed and forbidden dipole transitions, adapted from Ref. [192], and (b) schematic of the band offsets and changes in allowed transitions with alloying in ZnO, In 2 O 3 , and In 2 O 3 (ZnO) n , adapted from Ref. [195].…”

Section: Discussionmentioning

confidence: 99%

“…This enables doped CdO to be rather transparent at visible frequencies, even though the fundamental band gap would seem to be too low to allow this. In some other TCOs such as In 2 O 3 [135,170,192] [194] symmetry dictates that interband transitions between the top valence bands and the bottom conduction band are either dipole forbidden or have only minimal dipole matrix elements, as represented for In 2 O 3 in Fig. 14(a).…”

Section: Transparencymentioning

confidence: 99%

Conductivity in transparent oxide semiconductors

King

Veal

2011

J. Phys.: Condens. Matter

224

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

“…AE are dipole-forbidden [74]. After inclusion of the higher allowed optical transitions the absorption edge is shifted by about 0.8 eV.…”

Section: γ (T ) γ (A )mentioning

confidence: 99%

Ab‐initio theory of semiconductor band structures: New developments and progress

Bechstedt

Fuchs

Kresse

2009

Physica Status Solidi (b)

124

View full text Add to dashboard Cite

Organic fluorescent molecules are infiltrated in the channels of zeolite L nanocrystals, thus creating organic–inorganic fluorescent nanoparticles. Combined with dielectric matrices, these fluorescent nanopigments open the way to the realization of novel optical devices. In this paper, the optical measurement of the quantum yield of fluorescent zeolites by means of a precise and reliable diffuse reflectance technique is presented. Several possible factors that may affect the fluorescence quantum yield are also investigated.

show abstract

Nature of the Band Gap ofIn2O3Revealed by First-Principles Calculations and X-Ray Spectroscopy

Cited by 607 publications

References 29 publications

High Electron Mobility Thin‐Film Transistors Based on Solution‐Processed Semiconducting Metal Oxide Heterojunctions and Quasi‐Superlattices

High Electron Mobility Thin‐Film Transistors Based on Solution‐Processed Semiconducting Metal Oxide Heterojunctions and Quasi‐Superlattices

Conductivity in transparent oxide semiconductors

Ab‐initio theory of semiconductor band structures: New developments and progress

Contact Info

Product

Resources

About