We have developed a semiquantitative model based on Ostwald ripening to explain observed trends in both the carrier trapping lifetime and bulk resistivity when low-temperature-grown gallium arsenide is partially annealed. The effects of both point defects and precipitates are described independently, representing two distinct types of recombination center. The model predicts previously observed and hitherto unexplained anomalous features in the carrier lifetime and resistivity trends as the anneal temperature is increased. The predictions are supported by experimental measurements of the point defect concentration and precipitate parameters, using x-ray diffraction and transmission electron microscopy imaging, respectively.

• Received 21 February 2006

DOI:https://doi.org/10.1103/PhysRevB.73.195201