In our contribution we present the fabrication of Si_{1-x}Ge_x alloy by ion-implantation and millisecond flash lamp annealing. The 100 keV Ge ions at the fluence of 10×10^{16}, 5×10^{16}, and 3×10^{16} cm^{-2} were implanted into monocrystalline (100)-oriented Si wafers covered by 50 nm thermal oxide. In the consequence, the 50 nm amorphous Ge rich Si layers were obtained. The recrystallization of the implanted layers and the Si_{1-x}Ge_x alloying were accomplished by flash lamp annealing with the pulse duration of 20 ms. Flash lamp treatment at high energy densities leads to local melting of the Ge-rich silicon layer. Then the recrystallization takes place due to the millisecond range liquid phase epitaxy. Formation of the high quality monocrystalline Si_{1-x}Ge_x layer was confirmed by the μ-Raman spectroscopy, the Rutherford backscattering channeling and cross-sectional transmission electron microscopy investigation. The μ-Raman spectra reveal three phonon modes located at around 293, 404, and 432 cm^{-1} corresponding to the Ge-Ge, Si-Ge and Si-Si in the Si_{1-x}Ge_x alloy vibrational modes, respectively. Due to much higher carrier mobility in the Si_{1-x}Ge_x layers than in silicon such system can be used for the fabrication of advanced microelectronic devices.
AlN nanocrystalline layers and superstructures are used in the modern optoelectronic technology as reflecting mirrors in semiconductor lasers. In the present work the properties of AlN films prepared by sputtering methods from an AlN target in reactive Ar + N plasma were investigated. The characterisation was performed with HRTEM, SEM, glancing angle XRD and RBS methods. The present measurements confirmed the polycrystalline structure of AlN layers and enabled the evaluation of their grain size. The roughness and thickness of the layers were additionally determined by ellipsometric and profilometric measurements.
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Superconducting layers in silicon and germanium are fabricated via gallium implantation through a thin SiO_2 cover layer and subsequent rapid thermal annealing. Gallium accumulation at the SiO_2/Si and SiO_2/Ge interfaces is observed but no pure gallium phases were found. In both cases superconducting transition occurs around 6-7 K which can be attributed to the metallic conducting, gallium rich interface layer. However, the superconducting as well as the normal-state transport properties in gallium overdoped silicon or germanium are different.
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