Electrical compensation via vacancy-donor complexes in arsenic-implanted and laser-annealed germanium

Highly n-type Ge attained by shallow As implantation and excimer laser annealing was studied with positron annihilation spectroscopy and theoretical calculations. We conclude that a high concentration of vacancy-arsenic complexes was introduced by the doping method, while no sign of vacancies was seen in the un-implanted laser-annealed samples. The arsenic bound to the complexes contributes substantially to the passivation of the dopants. Published by AIP Publishing.