Short high-power laser pulses have been used for annealing of semiconducting layers, amorphised by ion implantation. For ion-implanted samples, laser annealing can be used for reconstruction and correction of lattice distortions and for inducing a redistribution of dopants. The structure of a laser-irradiated sample of a-Si amorphised by ion implantation depends on its initial structure and on the laser-pulse energy density [1-3]. Damage in Si caused by the implantation and annealing processes was studied for different kinds of implanted ions. Implantation with elements of IVA group is especially interesting, in view of the possible formation of Si-Ge and Si-Sn layers.
The presented paper reports in detail the defect structure induced by the nanosecond laser pulse with different energy density in Ge implanted silicon crystal. We observe changes of the annealed layer in dependence on the value of the energy density of laser beam. The redistribution of the dopant and its influence on the recrystallisation process of thin near-surface layer is discussed. To study the annealed areas we applied the high-resolution electron microscopy, X-ray section topography, atomic force microscopy and optical microscopy. Experimental findings are taken to determine more details of defects formed in Ge implanted Si crystal and to full characterization of the structural changes caused by the LPA.
References
[1] D. Klinger, M. Lefeld-Sosnowska, J. Auleytner, D. Żymierska, L. Nowicki, A. Stonert, S. Kwiatkowski, J. Alloys Compd. 328 (2001) 242
[2] Handbook of Crystal Growth 3, Thin Films and Epitaxy, ed. D.T.J. Huerle, 1994, p. 330.
[3] R.F. Wood, G.E. Gellison, Semicond. Semimet. 23 (1984) 115.
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