Recombination activity of manganese in p- and n-type crystalline silicon

Silicon wafers implanted with low doses of manganese were annealed at 900 °C to distribute the Mn throughout the sample volume, and were subjected to carrier lifetime measurements. The Mn centres thus introduced were found to decrease the recombination lifetime in both n- and p-type silicon, although the impact was greater in p-type silicon for resistivities near 1 ohm cm. For both p- and n-type samples, the bulk lifetime decreased approximately in proportion to the Mn implantation dose. Comparison with the known effects of other metals on the carrier lifetime in p-type silicon suggest that Mn is less detrimental than point-like Fe or Cr impurities, but more dangerous than Cu or Ni, which tend to precipitate. In n-type silicon on the other hand, Mn was found to have similar recombination activity to Fe, Ni and Cu.