Nickel-platinum alloy monosilicidation-induced defects in n-type silicon

Electrically active defects induced by the formation of nickel-platinum alloy monosilicide (formed at 600-800 degrees C) has bean studied in n-type silicon using deep level transient spectroscopy and transmission electron microscopy measurements. A Ni-related electron trap level at E-c - 0.42 eV is observed after silicidation at 600 degrees C or above and a Pt-related electron trap level at E-c--0.50 eV is detected after silicidation at 700 degrees C or above. Two hole trap levels at E-v +0.22 and E-v +0.28 eV are also detected, E-v +0.22 eV level for silicidation at 700 degrees C or above and E-v +0.28 eV level for 600 degrees C silicidation. For the sample silicided at 600 degrees C, an additional electron trap level (located at E-c - 0.16 eV) with a broad spectral peak is detected in the near-surface region (<0.65 mu m) of the sample in which some {311} type defects of 50-100 Angstrom long are also observed. Most of observed electrically active defects have been found to be present in near-surface regions (<2 mu m). Lowest total defect concentration is observed in the sample silicided at 700 degrees C where lowest reverse saturation current is also observed, indicating that the Ni(Pt) monosilicidation-induced electrically active defects are effective recombination/generation centers. (C) 2000 American Institute of Physics. [S0003-6951(00)02523-7].