Passivation of n and p dopants in ion-implanted GaAs by a ²D⁺ plasma

Strong n but weak p-carrier passivation was observed when Si- and Mg-implanted/annealed GaAs samples were exposed to a 2D plasma under identical conditions. Even though a discrete band of dislocation loops was present in both the samples, the 2D distribution in the two cases was remarkably different. In the Si-implanted sample the 2D followed the carrier distribution, whereas in the Mg-implanted sample it followed the distribution of dislocation loops. Phenomenological mechanisms of 2D interaction with dopants/dislocations in GaAs are postulated.