Deuterium diffusion and trapping in hydrothermally grown single crystalline ZnO

Secondary ion mass spectrometry is employed to investigate diffusion of H2 implanted in hydrothermally grown single crystal ZnO. Diffusion profiles have been studied after 30 min isochronal heat treatments from 100 to 400 °C and evaluated using three different models: the infinite source model, a solid solubility limited model, and a trap limited model. Only the latter one reproduces closely the measured values. From this model an activation energy Ea=0.85 eV is extracted, and it is speculated that trapping may be a source of the discrepancies between the reported values of Ea in the literature.