TiO₂-Coated Transparent Conductive Oxide (SnO₂:F) Films Prepared by Atmospheric Pressure Chemical Vapor Deposition with High Durability against Atomic Hydrogen

Abstract

We construct boundary states for supertubes in the flat spacetime. The T-dual objects of supertubes are moving spiral D1-branes (D-helices). Since we can obtain these D-helices from the usual D1-branes via null deformation, we can construct the boundary states for these moving D-helices in the covariant formalism. Using these boundary states, we calculate the vacuum amplitude between two supertubes in the closed string channel and read the open string spectrum via the open closed duality. We find there are critical values of the energy for on-shell open strings on the supertubes due to the non-trivial stringy correction. We also consider supertubes in the type IIA Gödel universe in order to use them as probes of closed timelike curves. This universe is the T-dual of the maximally supersymmetric type IIB PP-wave background. Since the null deformations of D-branes are also allowed in this PP-wave, we can construct the boundary states for supertubes in the type IIA Gödel universe in the same way. We obtain the open string spectrum on the supertube from the vacuum amplitude between supertubes. As a consequence, we find that the tachyonic instability of open strings on the supertube, which is the signal of closed time like curves, disappears due to the stringy correction.

Recent developments in TiO2 as n- and p-type transparent semiconductors: synthesis, modification, properties, and energy-related applications

“…Among the different TiO 2 deposition techniques, CVD offers several advantages, including purity of the coating, moderately low cost compared to other vacuum-based techniques, versatility to produce different morphologies, and good adhesion to the substrate [117][118][119][120]. Mills et al [121] fabricated a series of novel CVD films of titanium (IV) oxide of different thicknesses in the range of 10-91 nm on quartz substrate by reacting titanium (IV) chloride and ethyl acetate.…”

Properties of TiO2‐based transparent conducting oxides

“…For example, electrodes for blue LEDs and solar cells are promising applications of TNO. In terms of the chemical stability, film stability under a hydrogen plasma may be an advantage over ITO, 67 since TiO 2 is reported to be resistant to atomic hydrogen during depositing amorphous Si for solar cells 68, 69. Furthermore, TNO is a d‐electron based TCO (Fig.…”

“…For example, the use of a TCO with a refractive index matching with that of GaN would significantly increase the external quantum efficiency of blue GaN LEDs 8–10. Furthermore, careful selection of a TCO, considering its transmittance in the infrared region and work function, would improve the efficiency of solar cells 11 and OLEDs.…”

TiO2-based transparent conducting oxides; the search for optimum electrical conductivity using a combinatorial approach

“…6 TiO 2 is inexpensive, non-toxic, chemically stable over a wide range of pH and electrically stable over a wide range of voltage. The benets of improving TiO 2 thin-lms for TCO applications are clear given the material's enhanced impermeability, acid stability, 28 hydrogen radical exposure stability 29,30 and long wavelength transparency when compared with traditional materials such as In 2 O 3 , SnO 2 , CdO and ZnO. [7][8][9][10][11][12][13][14][15][16][17][18][19][20][21][22][23][24][25][26] For several years the bulk of transparent conducting oxide (TCO) research has focused on improving SnO 2 , 27 with signicant improvement now unlikely.…”