A new process to manufacture thin SiGe and SiGeC epitaxial films on silicon by ion implantation and excimer laser annealing

Abstract

Epitaxial Si 1− y C y and Si 1− x− y Ge x C y alloy layers are grown on monocrystalline silicon substrates by multiple energy ion implantation of Ge and C into single Si crystals followed by pulse excimer laser annealing. The properties of the alloy layers are determined precisely using spectroscopic ellipsometry (SE), X-ray diffraction (XRD) and Rutherford backscattering (RBS) techniques. We show that annealing energy densities higher than 2 J/cm 2 result in monocrystalline epitaxial layers with low quantity of defects. The lattice contraction due to the carbon inclusion increases with the implanted C concentration up to about 1.1%. For higher values a more complex behavior is observed with partial (or total) relaxation of the layer and/or carbide formation. With optimized condition, the growing of pseudomorphic epitaxial layers, from group IV semiconductor alloys was successful on large areas (1 J/cm 2 over 40 cm 2 in one pulse).