The substitutional gold concentration introduced in silicon by a diffusion step between 850 and 1000 °C was measured by deep level transient spectroscopy both in floating zone (FZ) and Czochralski (Cz) silicon containing different dislocation densities. The comparison, in the same sample, of dislocated and undislocated regions allows the efficiency of dislocations as sinks for self‐interstitials &ggr; to be measured as a function of diffusion temperature. In FZ silicon &ggr; was found independent of temperature whereas in Cz silicon a remarkable temperature dependence for &ggr; was observed which can be attributed to the release of dislocations by a thermally stimulated climbing mechanism from obstacles (i.e., oxygen segregation or precipitation). ©1995 American Institute of Physics.