Electronic structure of oxidized SiC(0001) studied by inverse photoemission spectroscopy

Ostendorf, R.; Wulff, K.; Benesch, C.; Zacharias, H.

doi:10.1016/j.susc.2006.02.064

Cited by 5 publications

(2 citation statements)

References 21 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The experimental values for the gap are 2.0 eV for 6H-SiC(0001) √ 3 × √ 3 [19,23] and 1.0 eV [22] or 1.2 eV [24] for 6H-SiC(0001)3 × 3. Recently, a value of U = 2.2 ± 0.2 eV has been derived for 4H-SiC(0001) √ 3 × √ 3 [44]. The values of U may also be estimated from the Coulomb repulsion and the screening response to charge transfers.…”

Section: Mott-hubbard Picture and Quasi-particle Approachmentioning

confidence: 99%

Electron correlation effects on SiC(111) and SiC(0001) surfaces

Bechstedt¹,

Furthmüller²

2004

J. Phys.: Condens. Matter

View full text Add to dashboard Cite

The possibility is discussed that, independent of the polytype, large electronic correlation effects give rise to semiconducting SiC surfaces with [111] or [0001] orientations. The most important surface translational symmetries ( √ 3× √ 3)R30 • and 3×3 are considered. The discussion is based on the detailed knowledge of the surface atomic geometries and the electronic structures derived for these geometries using a local density approximation for exchange and correlation. It is argued that the resulting half-filled, weakly dispersive dangling-bond bands within the fundamental gaps are split according to a Hubbard interaction parameter U , and that the surface systems undergo a Mott-Hubbard transition. Such a physical picture provides a qualitatively correct account of the single-particle excitation spectra either inferred from angleresolved photoemission and inverse photoemission experiments or obtained from scanning tunnelling spectroscopy. The gap opening and hence the Hubbard U parameter are discussed in terms of their dependence on the surface reconstruction as well as the SiC polytype.

show abstract

Section: Mott-hubbard Picture and Quasi-particle Approachmentioning

confidence: 99%

Electron correlation effects on SiC(111) and SiC(0001) surfaces

Bechstedt¹,

Furthmüller²

2004

J. Phys.: Condens. Matter

View full text Add to dashboard Cite

show abstract

“…7(a)), UPS shows photoemission from surface states all the way up to the Fermi level (E F ). Surface states in the band gap of SiC of this nature have been previously observed in several photoemission studies of 6H-SiC (0001) surfaces [29][30][31][32][33]. These studies combined with our prior studies of hydrogen desorption from (0001)/(111) SiC surfaces [18] have shown that these surface states are attributable to surface Si-Si bonds arising due to the presence of Si adatoms on the (0001)/(111) SiC surface.…”

mentioning

confidence: 96%

Photoemission investigation of the Schottky barrier at the Sc/3C-SiC (111) interface

King

Nemanich

Davis

2014

Phys. Status Solidi B

View full text Add to dashboard Cite

The Schottky barrier and interfacial chemistry for interfaces formed by evaporation of Sc onto 3C-SiC (111)-(1x1) surfaces at 600 8C has been investigated using in situ X-ray and ultraviolet photoelectron spectroscopy (XPS and UPS) and low energy electron diffraction (LEED). Sc was observed to grow in a two-dimensional manner and exhibit a (1x1) LEED pattern up to thicknesses of $2 nm beyond which diffraction patterns were no longer observable. XPS measurements of these same films showed a clear reaction of Sc with the 3C-SiC (111)-(1x1) surface to form a ScSi x and ScC x interfacial layer in addition to the formation of a metallic Sc film. XPS measurements also showed the deposition of Sc induced $0.5 eV of upward band bending resulting in a Schottky barrier of 0.65 AE 0.15 eV. More recently, Sc has garnered significant interest as an electrical contact metal [1], conductive dislocation reducing buffer layer [3,4], and alloying agent with aluminum nitride (AlN) and gallium nitride (GaN) for a variety of piezoelectronic [5][6][7], thermoelectric [8], ferroelectric [9], and optoelectronic applications [10][11][12]. This interest is primarily a result of the high solubility and close lattice matching of Sc with wurtzite structure AlN and GaN (a 0 ¼ 0.3111 and 0.3189 nm), high thermal stability, ductility, and relative ease of deposition [1]. Sc also exhibits reasonably close lattice matching to the (111)/(0001) basal plane of cubic and hexagonal silicon carbide (SiC, a 0 ¼ 0.308 nm). Therefore, Sc could also serve as a potential Ohmic or Schottky contact for high temperature, power, and frequency SiC based electronic devices and as a conductive buffer layer for GaN heteroepitaxy on SiC substrates. For these specific applications, the band alignment of Sc to SiC will play a significant

show abstract