Disorder saturation in heavy ion implanted semiconductors

Abstract

Studies of ion implantation induced disorder production in Si, GaAs and InP as a function of heavy ion fluence are examined for similarities. In all cases disorder increases rapidly then reaches a quasi saturation with increasing fluence. The 'knee' at which the transition to quasi-saturation occurs is identified, from disorder-depth distribution function measurements, as corresponding to production of a continuous amorphous layer. The thickness of this layer is found, for all three substrates and a range of ion species and energies to be well described by the relations: X=Xd+(2.7×0.5)ΔXd where Xd is the mean damage depth and ΔXd is the standard deviation of damage profile. This allows reasonable prediction to be made of critical fluences required for initial amorphous layer production. Show more