REALIZATION OF SI1-X-YGEXCY SI HETEROSTRUCTURES BY PULSED-LASER INDUCED EPITAXY OF C+ IMPLANTED PSEUDOMORPHIC SIGE FILMS AND OF A-SIGEC-H FILMS DEPOSITED ON SI(100)/

Si1-x-yGexCy/Si heterostructures are realized by pulsed laser induced epitaxy (PLIE) from C+ implanted pseudomorphic Si0.84Ge0.16 films and from hydrogenated amorphous SiGeC films deposited on Si(100). The lase r-treated samples are examined by electron channelling, energy dispers ive X-ray analysis, Rutherford backscattering spectroscopy and ion cha nnelling, X-ray diffraction, secondary ion mass spectrometry, and infr ared and Raman spectroscopy. We show that PLIE occurs when the laser f luence exceeds a threshold for which the liquid-solid interface reache s the crystalline substrate at each laser pulse. Above this threshold, germanium and carbon atoms diffuse inside the melted layer, and carbo n incorporation in substitutional sites increases with the laser fluen ce and the number of pulses. The resulting SiGeC layers are pseudomorp hic.