Fabrication of $Si_{1-x}Ge_x$ Alloy on Silicon by Ge-Ion-Implantation and Short-Time-Annealing

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 $10 \times 10^{16}, 5 \times 10^{16}$, and $3 \times 10^{16} cm^{-2}$ 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.