Low-temperature damage formation in ion implanted InP

Abstract

Damage formation in ion implanted InP is studied by quasi–in situ Rutherford backscattering spectrometry (RBS) in channelling configuration. Subsequent implantation steps are performed at 15K each followed by immediate RBS analysis without changing the environment or the temperature of the sample. 30keV He, 150keV N and 350keV Ca ions were applied. The depth distribution of damage is in good agreement with that calculated with the SRIM code. The evolution of damage at the maximum of the distribution as a function of the ion fluence is described assuming damage formation within single ion impacts and stimulated growth of damage when the collision cascades start to overlap with cross sections σd and σg, respectively. These cross sections are found to depend on the primary energies deposited in the displacement of lattice atoms and in electronic interactions calculated with the SRIM code. The obtained empirical formulas are capable to represent the experimental results for different III–V compounds implanted at 15K with various ion species.