Raman spectroscopy of Si 1 − x − yGe xC y layers obtained by pulsed laser induced epitaxy

Abstract

In this paper we present an investigation of pulsed laser induced epitaxy (PLIE) to obtain epilayers of Si 1 − x − y Ge x C y on top of Si substrate by annealing non-crystalline SiGeC layers. Si 1 − x − y Ge x C y Si heterostructures were formed from C + implanted pseudomorphic Si 0.84Ge 0.16 films and from hydrogenated amorphous SiGeC films deposited on Si(100). All samples were annealed in vacuum by XeCl excimer laser pulses. An analysis of the annealing process is presented, based on a detailed Raman study of the laser treated samples. The interpretation is corroborated by additional techniques: Rutherford backscattering spectroscopy, X-ray diffraction, and secondary ion mass spectroscopy (SIMS). Raman scattering is shown to be a relatively simple, non-destructive technique, to analyze the growth process, i.e. parameters such as crystallization, SiGeC layer depth, Ge content, and C incorporation in substitutional sites.