Passivation of the dominant deep level (EL2) in GaAs by hydrogen

We showed that hydrogen incorporated into single crystals of GaAs (by exposure of the crystals to hydrogen plasma) renders the major deep donor level (EL2) located at 0.82 eV below the conduction band at room temperature electronically inert. We attribute this passivation process to the interaction of hydrogen with the unsaturated bonds of the antisite AsGa defect (believed to be responsible for EL2) leading to the formation of stable As–H bonds.