Mechanical strain and damage accumulation were studied in single crystals which had been implanted with Ne ions, to doses ranging from 1016 to 1017/cm2, at 200 to 600C. Two distinct layers were found in the implanted material. One was a near-surface layer that was less than 0.2μm thick, and within which no extended defects were observed. The other was a buried layer, greater than 0.5μm thick, which contained a dense array of dislocation loops and defect clusters. Cross-sectional transmission electron microscopy revealed a distribution of small spherical cavities which were assumed to be filled with Ne. These had diameters below 4mm, and extended through the entire depth of the implanted layer. High-resolution X-ray diffraction analysis revealed the presence of a positive strain (expansion); regardless of the implantation dose and temperature. The findings were explained in terms of a model which assumed that vacancy-type defects were consumed during the formation of Ne bubbles.

Strain Development and Damage Accumulation during Neon-Ion Implantation into Silicon at Elevated Temperatures. C.A.Cima, H.Boudinov, J.P.de Souza, Y.Suprun-Belevich, P.F.P.Fichtner: Journal of Applied Physics, 2000, 88[4], 1771-5