Synthesis of TiO2 coatings by thermal oxidation with a suitable cooling process for improved wettability

This paper reviews our recent work on ultrahigh-temperature oxidation of 4H-SiC(0001) surfaces. Our rapid thermal oxidation experiments demonstrated the reaction-limited linear growth at temperatures ranging from 1200 to 1600°C. The Arrhenius plot of linear growth rate of thermal oxidation can be fitted by a linear line, and the activation energy of oxide growth in dry O2 oxidation was estimated to be 2.9 eV. We also found that unintentional oxidation during the cooling down process severely degrades SiO2/SiC interface properties, resulting in positive flatband voltage shift (VFB) and hysteresis in capacitance-voltage (C-V) characteristics regardless of oxidation temperature. By effectively suppressing oxide growth during the cooling process, we have clarified that SiO2/SiC interface properties depend on oxidation temperature and the lowest interface state density was obtained for the oxide formed at 1450°C.

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Structural, Optical and Photoelectrochemical Properties of Cuprous Oxide Synthesized by Low Temperature Thermal Oxidation

Material Science Research India ◽

10.13005/msri/130101 ◽

2016 ◽

Vol 13 (1) ◽

pp. 01-06

Author(s):

A. A Ogacacho ◽

B. O. Aduda

Keyword(s):

Thin Films ◽

Low Temperature ◽

Thermal Oxidation ◽

Ultrathin Films ◽

Cuprous Oxide ◽

Photoelectrochemical Properties ◽

X Ray Diffraction ◽

Cooling Process ◽

X Ray ◽

Dominant Phase

Ultrathin films (50-150nm thick) cuprous oxide (Cu2O) thin films were deposited by low temperature thermal oxidation technique. The structural, optical and photoelectrochemical properties of the thin films were investigated. X-ray diffraction (XRD) and high resolution scanning electron microscope (SEM) was used to study the phase composition and the thin films’ microstructure respectively. XRD results showed that Cu2O was the dominant phase albeit some trace CuO peaks were also observed indicating surface formation of an extremely layer of CuO probably during the cooling process following either deposition or during the annealing steps. SEM showed a highly nanostructure consisting long narrow nanorods with broadening to the surface but with extremely narrow, sharp cylindrical roots standing on the substrate. Photoelectrochemical properties of the films were studied via a standard three electrode using a saturated calomel cell (SCE).

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Bulk standards for low-temperature biological x-ray microanalysis

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100111525 ◽

1984 ◽

Vol 42 ◽

pp. 282-283

Author(s):

P. Echlin ◽

M. McKoon ◽

E.S. Taylor ◽

C.E. Thomas ◽

K.L. Maloney ◽

...

Keyword(s):

Phase Separation ◽

Low Temperature ◽

Analytical Method ◽

Salt Solutions ◽

Absolute Concentration ◽

Cooling Process ◽

X Ray ◽

The Absolute ◽

Analytical Procedures ◽

Electrical Conductors

Although sections of frozen salt solutions have been used as standards for x-ray microanalysis, such solutions are less useful when analysed in the bulk form. They are poor thermal and electrical conductors and severe phase separation occurs during the cooling process. Following a suggestion by Whitecross et al we have made up a series of salt solutions containing a small amount of graphite to improve the sample conductivity. In addition, we have incorporated a polymer to ensure the formation of microcrystalline ice and a consequent homogenity of salt dispersion within the frozen matrix. The mixtures have been used to standardize the analytical procedures applied to frozen hydrated bulk specimens based on the peak/background analytical method and to measure the absolute concentration of elements in developing roots.

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