Abstract
Dislocations in semiconductors can be strongly affected by a hydrogen plasma; core states may be passivated and mobility changed. For example, in silicon the activation barrier for dislocation motion drops by 1.0 eV upon exposure to H plasma for one hour at 470-540 °C. If such an effect were to be found in diamond, a simple scaling argument would yield an activation energy of 1.9 eV. Here, density functional calculations have been applied to the 90° partial dislocation in diamond which confirm this prediction. They also show that, energetically, the soliton model for motion of the 90° partial is as viable as the strained-bond model.