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Materials Science and Engineering

Electrical & Computer Engineering Faculty Publications

Series

Crystalline materials

Publication Year

Articles 1 - 3 of 3

Full-Text Articles in Engineering

Nonthermal Laser-Induced Formation Of Crystalline Ge Quantum Dots On Si(100), M. S. Hegazy, H. E. Elsayed-Ali Jan 2008

Nonthermal Laser-Induced Formation Of Crystalline Ge Quantum Dots On Si(100), M. S. Hegazy, H. E. Elsayed-Ali

Electrical & Computer Engineering Faculty Publications

The effects of laser-induced electronic excitations on the self-assembly of Ge quantum dots on Si (100) - (2×1) grown by pulsed laser deposition are studied. Electronic excitations due to laser irradiation of the Si substrate and the Ge film during growth are shown to decrease the roughness of films grown at a substrate temperature of ∼120 °C. At this temperature, the grown films are nonepitaxial. Electronic excitation results in the formation of an epitaxial wetting layer and crystalline Ge quantum dots at ∼260 °C, a temperature at which no crystalline quantum dots form without excitation under the same deposition conditions. …


Melting And Solidification Study Of As-Deposited And Recrystallized Bi Thin Films, M. K. Zayed, H. E. Elsayed-Ali Jan 2006

Melting And Solidification Study Of As-Deposited And Recrystallized Bi Thin Films, M. K. Zayed, H. E. Elsayed-Ali

Electrical & Computer Engineering Faculty Publications

Melting and solidification of as-deposited and recrystallized Bi crystallites, deposited on highly oriented 002-graphite at 423 K, were studied using reflection high-energy electron diffraction (RHEED). Films with mean thickness between 1.5 and 33 ML (monolayers) were studied. Ex situ atomic force microscopy was used to study the morphology and the size distribution of the formed nanocrystals. The as-deposited films grew in the form of three-dimensional crystallites with different shapes and sizes, while those recrystallized from the melt were formed in nearly similar shapes but different sizes. The change in the RHEED pattern with temperature was used to probe the melting …


Optical And Electrical Properties Of Cualse² Thin Films Obtained By Selenization Of Cu/Al/Cu... Al/Cu Layers Sequentially Deposited, J. C. Bernède, S. Marsillac, C. El Moctar, A. Conan Jan 1997

Optical And Electrical Properties Of Cualse² Thin Films Obtained By Selenization Of Cu/Al/Cu... Al/Cu Layers Sequentially Deposited, J. C. Bernède, S. Marsillac, C. El Moctar, A. Conan

Electrical & Computer Engineering Faculty Publications

Optical and electrical properties of CuAlSe2 thin films obtained by selenization of Cu/Al/Cu...Al/Cu layers sequentially deposited have been investigated. It is shown that the expected energy gap (2.67 eV) is measured for well crystallized films, whereas a slightly higher value is measured for films not so well crystallized. Raman diffusion also shows differences between well and poorly crystallized films with peaks corresponding to the reference powder for the former samples. A p-type conductivity is found whatever the crystalline quality of the samples. The conductivity of the films depends also strongly on their crystalline properties. When the films are badly …