Helium-implanted silicon: a study of bubble precursors

The interaction of helium atoms with the radiation damage transferred to silicon single crystal by He+ implantation at a dose of 5x10(sup 15) cm-2 and energy of 20 keV, and liquid-nitrogen temperature is analyzed using a variety of complementary methods during and after treatments. To determine the dissociation kinetics of helium from the defects and to plan appropriate heat treatments for the other approaches, thermal programmed desorption was employed. The results are discussed.