Comparative study of ion implantation caused anomalous surface damage in silicon studied by spectroscopic ellipsometry and Rutherford backscattering spectrometry

Damage created by ion implantation of 150 keV Ne+ and 800 keV Ar+ ions in s ingle-crystalline silicon was characterized using Spectroscopic Ellipsometr y (SE) and Rutherford Backscattering Spectrometry (RBS) in combination with channeling. Results from both methods unambiguously show the presence of a heavily damaged thin layer at the surface that is not predicted by TRIM ca lculations. The amorphization rate at the surface was found to be proportio nal to the nuclear energy deposition at the surface. It is demonstrated tha t SE cross-checked with RES could be used for quantitative and accurate eva luation of the thickness of the damaged surface layer. The formation of thi s thin amorphous layer could be attributed to the redistribution of Si inte rstitials produced by the implantation process from the buried damaged regi on towards the surface and to a subsequent segregation process CN. Fukarek et al., Nucl. Instr. and Meth. B 127/128 (1997) 879). (C) 1999 Elsevier Sci ence B.V. All rights reserved.