Metal Vapor Vacuum Arc (MEVVA) pulse ion source [1] is used for high temperature rhenium silicide creation on silicon wafer. Some phases of this silicide have good perspectives for semiconductor industry. For example, rhenium disilicide (ReSi₂) is semiconductor with ΔE ≈ 0.1 eV. Previously it was shown that rhenium silicide can be synthesized by Re⁺ ion implantation without extra heat treatment (annealing). For our experiments pulse ion beam accelerated by 8.6 kV is used. Pulse length is 3 ms and current density is 4 mA/cm². During experiments ion beam repetition rate is varied from 1/3 pps to 5 pps.

       As a new result we observed the nanostructures (nanoclusters) created inside the bombarded layer of silicon.  The profile of space distribution of the clusters correlates with implanted Re atoms distribution (maximum of this distribution coincides with R_p). Using Auger probe we investigated the composition of nanoclusters and observed an enrichment of them by Re atoms. The ratio of Si and Re atoms inside and outside of clusters is presented in dependence on bombardment conditions. It was found that the increasing of ion beam repetition rate leads to the increasing of cluster concentration on the wafer surface for same dose implanted. Other clusters parameters (composition, dimensions etc.) and their dependence on ion beam characteristics are presented as well. Taking into account the previously published results of nanostructures synthesis by ion beams, we present a model for explanation of the nanoclusters formation phenomena.

[1] T.Kulevoy, N.Gerasimenko, D.Seleznev, G.Kropachev, A.Kozlov, R.Kuibeda, P.Yakushin, S.Petrenko, N.Medetov and O.Zaporozhan. ITEP MEVVA ion beam for rhenium silicide production. Rev. Sci. Instrum. 81, 02B905 (2010)

Nikolai Gerasimenko*, Moscow Institute of Electronic Technology, Russian Federation
Timur Kulevoy, Institute for Theoretical and Experimental Physics, Moscow, Russian Federation
Pavel Yakushin, Institute for Theoretical and Experimental Physics, Moscow, Russian Federation
Dmitry Selesnev, Institute for Theoretical and Experimental Physics, Moscow, Russian Federation
Nurlan Medetov, Moscow Institute of Electronic Technology, Russian Federation
Olga Zaporozhan, Moscow Institute of Electronic Technology, Russian Federation

*presenting author