V. Muñoz-Sanjosé

Temperature dependence of the direct bandgap and transport properties of CdO

Temperature-dependent optical absorption, Hall effect, and infrared reflectance measurements have been performed on as-grown and post-growth annealed CdO films grown by metal organic vapor phase epitaxy on sapphire substrates. The evolution of the absorption edge and conduction electron plasmon energy with temperature has been modeled, including the effects arising from the Burstein-Moss shift and bandgap renormalization. The zero-temperature fundamental direct bandgap and band edge effective mass have been determined to be 2.31+/-0.02 eV and 0.27+/-0.01m(0), respectively. The associated Varshni parameters for the temperature dependence of the bandgap are found to be a alpha = 8 x 10(-4) eV/K and beta = 260 K.

Electron mobility in CdO films

Electron mobility in degenerate CdO thin films has been studied as a function of carrier concentration. The “optical” mobility has been determined from infrared reflectance measurements of the conduction band plasmon lifetime. The acquired values vary from ∼209 to ∼1116 cm2 V-1 s-1 for carrier concentrations between 2.5× 1020 and 2.6× 1019 cm-3. Ionized impurity scattering is shown to be the dominant effect reducing the intra-grain mobility of the electrons at room temperature. The transport mobilities from Hall effect measurements range between 20 and 124 cm2 V-1 s-1 which are much lower than the optical mobilities. Simulation of grain boundary scattering-limited mobility is commonly based on models that assume a depletion layer at the boundaries which causes an inter-grain potential barrier. These models are found not to be applicable to CdO as it has been previously shown to have surface electron accumulation. Therefore, simulation of the transport mobility has been performed using the Fuchs-Sondheim...

Semiconductor-metal transitions in liquid In 100 − x Se x alloys: A concentration-induced transition

The electronic and structural properties of

Valence-band electronic structure of CdO, ZnO, and MgO from x-ray photoemission spectroscopy and quasi-particle-corrected density-functional theory calculations

{mathrm{In}}_{100ensuremath{-}x}{mathrm{Se}}_{x}

Surface band-gap narrowing in quantized electron accumulation layers

liquid alloys close to their melting points have been investigated by combining x-ray-absorption experiments with ab initio molecular-dynamics simulations. Extended x-ray-absorption fine-structure data have been acquired at both the In and Se K edges in a large concentration range

Observation of quantized subband states and evidence for surface electron accumulation in CdO from angle-resolved photoemission spectroscopy

(x=20%

Unification of the electrical behavior of defects, impurities, and surface states in semiconductors: Virtual gap states in CdO

to

Electronic structure of single-crystal rocksalt CdO studied by soft x-ray spectroscopies and ab initio calculations

x=50%

Ab-initio studies of electronic and spectroscopic properties of MgO, ZnO and CdO

of Se content). Ab initio molecular-dynamics simulations have been carried out at the two most extreme concentrations explored experimentally. Liquid InSe is found to retain a semiconducting behavior which results from a low-dimensional structure, reminiscent of that of the ambient solid phase, characterized by strong In-Se interactions within tetrahedral units. On the other side, the

X-ray photoemission studies of the electronic structure of single-crystalline CdO(100)

{mathrm{In}}_{80}{mathrm{Se}}_{20}