The precipitation and dissolution of monoclinic SiAs in samples which had been implanted with 1017 or 1.5 x 1017As+/cm2, was monitored at 800, 900, and 1050C by means of transmission electron microscopy and secondary neutral mass spectrometry. It was found that the saturation concentration of mobile As, which diffused after equilibration with the monoclinic SiAs precipitates, could be described by: C(/cm2) = 1.3 x 1023exp[-0.42(eV)/kT]. This saturation concentration comprised various states of As which were in equilibrium with the monoclinic phase at the annealing temperature: such as electrically active and inactive mobile dopants. The present results indicated that the inactive As was in the form of clusters. The link between clustering, and the presence of small particles which were detected by transmission electron microscopic observations, was considered.

D.Nobili, S.Solmi, A.Parisini, M.Derdour, A.Armigliato, L.Moro: Physical Review B, 1994, 49[4], 2477-83