Interaction between the divacancy and hydrogen in silicon: Observation of fast and slow kinetics

摘要

The divacancy (V-2) is one of the fundamental defects in silicon. However, the interaction of V-2 with hydrogen is still not fully understood. In the present work, deep level transient spectroscopy (DLTS) results on hydrogen-assisted annealing of V-2 are presented. H+ ions were implanted with multiple energies into n-type Czochralski-grown samples, yielding uniform (box-like) concentration-versus-depth profiles of V-2 and hydrogen in the region probed by the DLTS measurements. The evolution kinetics of V-2 reveals two distinct processes: (i) a fast one attributed to dissociation of phosphorus-hydrogen pairs and reaction with highly mobile atomic H, and (ii) a slow one whose origin is not identified yet. During the slow process, we observe the formation of a hydrogen-related electronic state, labeled E.5* and positioned similar to 0.42 eV below the conduction band edge. The growth of E5* displays a close one-to-one proportionality with the loss of a V-2-related DLTS peak, presumably due to V2H, overlapping with that of the single negatively charged V-2. Published by AIP Publishing.