Full-text resources of PSJD and other databases are now available in the new Library of Science.
Visit https://bibliotekanauki.pl
Preferences help
Polish version English version Language
enabled [disable] Abstract
Number of results

Results found: 3

Number of results on page
first rewind previous Page / 1 next fast forward last

Search results

help Sort By:

help Limit search:
first rewind previous Page / 1 next fast forward last
1
Content available remote

Properties of~Rf Plasma Nitrided Silicon Thin Films at Different Rf Plasma Processing Powers

100%
Mohamed S., Raaif M., Abd El-Rahman A., Shaaban E.
Acta Physica Polonica A
|
2011
|
vol. 120
|
issue 3
552-557
EN
Nitrided surfaces and composition gradients in thin films exhibit interesting mechanical, electrical and optical properties. Therefore, silicon (Si) thin films were prepared by electron beam evaporation and nitrided by an inductively coupled rf plasma. The effects of successive plasma processing power on structural and optical properties as well as electrical resistivity were examined by different characterization techniques. The Si thin films were transformed gradually into nitrides compound thin films and the amount of nitrogen in the film increased with increasing the rf processing power. The Si nitrided films showed structural, optical and electrical properties that depend on the nitriding power. Increasing the rf plasma processing power caused amorphization, reduced the thickness, increased transmittance, increased resistivity and decreased the reflectance of the Si films. The electrical resistivity increased about eight orders of magnitude when the sample nitrided at 500 W. Different optical band gap were determined indicating the presence of different competing phases in the same film. The decrease in refractive index with plasma treatment power is attributed to the possible change in the bucking density as well as to the increase in the band gap.
2
Content available remote

Thermal Stability Criteria of Se_{80-x}Te_{20}Sb_{x} in Terms of Characteristic Temperatures and Kinetic Parameters

100%
Shaaban E., Elshaikh H., Soraya M.
Acta Physica Polonica A
|
2015
|
vol. 128
|
issue 3
358-366
EN
Thermal stability in terms of characteristic temperature and kinetic parameters of different compositions of glassy Se_{80-x}Te_{20}Sb_{x} (x=0, 2, 4, 6, 8, 10) have been investigated. Differential scanning calorimetry under nonisothermal conditions have been proposed to investigate thermal characteristic of these compositions. The thermal stability of these glasses was obtained in terms of various simple quantitative methods based on the characteristic temperatures, such as the glass transition temperature, T_{g}, the onset temperature of crystallization, T_{in}, the temperature corresponding to the maximum crystallization rate, T_{p}, and the melting temperature, T_{m}. Furthermore, the kinetic parameter K_{r}(T) was achieved as another indicator for thermal stability and its results about stability compared with those evaluated by other criteria. The results of both the criteria and the kinetic parameter K_{r}(T) confirm that the thermal stability increases with increase of Sb content. The results also refer to that: the glass transition T_{g}, activation energy of crystallization E_{p} and the frequency factor K_{0} were increased with the addition of Sb. These results have been discussed in terms of the average coordination number, cohesive energy and average heat of atomization.
3
Content available remote

Validity of Swanepoel's Method for Calculating the Optical Constants of Thick Films

100%
Shaaban E., Yahia I., El-Metwally E.
Acta Physica Polonica A
|
2012
|
vol. 121
|
issue 3
628-635
EN
Optical constants, dispersion and oscillator parameters of different thicknesses of amorphous Ge_{25}Cd_5Se_{70} films have been deposited onto glass substrates using thermal evaporation technique. The optical constants have been investigated by optical spectrophotometry measurements. The straight forward analysis proposed by Swanepoel, which is based on the use of the extremes of the interference fringes has been used in order to derive the refractive index and the film thickness in μm range. The refractive index could be extrapolated by the Cauchy dispersion relationship over the whole spectral range, which extended from 400 to 2500 nm. It is observed that, refractive index n increases with the film thickness. The possible optical transition is found to be allowed indirect transition with energy gap increase from 1.915 to 1.975 eV with increasing film thickness. The dispersion of the refractive index is discussed in terms of the Wemple-DiDomenico single oscillator model. The interband oscillator wavelength, the average oscillator strength, and the optical conductivity were estimated for different thicknesses of amorphous Ge_{25}Cd_5Se_{70} films.
first rewind previous Page / 1 next fast forward last
JavaScript is turned off in your web browser. Turn it on to take full advantage of this site, then refresh the page.