Identification by deuterium diffusion of a nitrogen-related deep donor preventing the p-type doping of ZnO

Deuterium diffusion is investigated in nitrogen-doped homoepitaxial ZnO layers. The samples were grown under slightly Zn-rich growth conditions by plasma-assisted molecular beam epitaxy on m-plane substrates and have a nitrogen content [N] varied up to 5x1018 at.cm-3 as measured secondary ion mass spectrometry (SIMS). All exposed radio-frequency deuterium plasma during 1h at room temperature. observed all epilayers while its penetration depth decreases the concentration increases. This strong evidence of mechanism limited trapping nitrogen-related trap. SIMS profiles are analyzed using two-trap model including shallow trap, associated with fast diffusion, deep related nitrogen. capture radius trap determined be 20 times smaller than value expected for nitrogen-deuterium pairs formed coulombic attraction between D+ acceptors. (N2)O donor proposed site accounts well small photoluminescence quenching recovery after deuteration ZnO:N epilayers. It also found that this defect far N-related highest studied samples.