STRUCTURE DISTURBANCES OF ION IMPLANTED SOLICON CRYSTALS

Zbigniew Swiatek1, Jan Bonarski1, Marek Michalec2 , Igor Fodchuk3, Ewa Beltowska-Lehman1, Ryszard Ciach1

1 Institute of Metallurgy and Materials Science, Polish Academy of Science, 25 Reymonta Str., 30-059 Krakow, Poland
2 Faculty of Chemistry, Jagiellonian University, 3 Ingardena Str. 30-060 Krakow, Poland, MICHALEC@Trurl.ch.uj.edu.pl
3 Chernivtsi State University, 2 Kotsyubinskogo Str. , 274012 Chernivtsi, Ukraine

Keywords: x-ray study, ion implantation, buried layers, near-surface-layers, stress evolution

 

The transmission electron microscopy, atomic force microscopy and x-ray study of structural and internal stress evolution in the ion implanted and annealed silicon single-crystal are presented. To prepare the samples, a half of (001)-oriented Si single-crystal (diameter - 2in., thickness - 250mm.) was implanted at room temperature with P ions at dose 61014cm-2 and 180keV energy and then divided in four parts perpendicularly to a boundary of the implanted and non-implanted areas. Three of the samples obtained in this way was annealed at 500oC for 6, 15 and 30 min., respectively. For the structural characterisation the x-ray measurements were carried out on an initial, an non-implanted and annealed, an as-implanted as well as an implanted and annealed material.

From the transmission electron microscopy and atomic force microscopy studies is it evident that the buried continuous sub-structure of modified material (amorphized layer) was formed. The buried amorphous-like layer contains some amount of single-crystal inclusions within its bulk. The time of annealing fundamentally influences on the quality of the a-Si/c-Si heterointerfaces, structural homogeneity of the layers and distribution of the stress field.

For layer by layer analysis of structural changes in near-surface-layers, a one- and two crystal spectrometer with setting of investigated crystal in the screw non-symmetric mode of Bragg diffraction were used. In this way the measurements for different x-ray penetration depths were carried out. In this work MoKa, MoKb and CoKa radiation in a diffraction profile and x-ray topography measurements were used, respectively. From the x-ray data analysis an average value of the lattice deformation and changed-in-sign deformation as well as effective depth of considerable deformation were estimated