STRUCTURAL AND ELECTRICAL STUDY OF EPITAXIALLY REALIGNED SB-DOPED POLYCRYSTALLINE SI FILMS

Epitaxial realignment of Sb-doped polycrystalline Si films deposited on Si substrates has been induced by rapid thermal annealing in the temperature range 1000-1 150-degrees-C. Structural and electrical characterization of the realigned layers has been carried out by means of Rutherford backscattering and channelling analysis, transmission electron microscopy and incremental sheet resistance in conjunction with Hall effect measurements. The realignment mode of the Sb-doped poly-Si films occurs by planar movement of the poly-Si-C-Si interface towards the film surface as in undoped samples. The realignment kinetics is enhanced by a factor of no more than 3 at high Sb doses. The electrically active Sb concentration in the realigned layers is 30% higher than the solid solubility limit of Sb in Si, indicating that equilibrium conditions are not reached during the rapid thermal processes.