Transient enhanced diffusion of B in silicon is modelled at temperatures down to 500 degreesC, using a simplified model of self-interstitial clusters to describe the time evolution of the self-interstitial supersaturation, S. The model is highly predictive, providing an accurate description of diffusion both in the peak and tail regions of B marker layers, over a wide range of annealing conditions. The model is well adapted for implementation into existing 2D commercial simulation tools. Fundamental parameters of atomic-scale B diffusion were extracted for the first time at T = 500 degreesC, under both intrinsic and extrinsic conditions. (C) 2005 Elsevier Ltd. All rights reserved.