Rapid thermal processing (RTP) is of increasing interest in silicon mainstream technology providing reduced thermal budget. In this paper the dopant diffusion behaviour during rapid thermal oxidation (RTO) is investigated, in particular the oxidation enhanced diffusion (OED). For diffusion monitoring, samples were fabricated by means of molecular beam epitaxy (MBE) to create sharp doping profiles with nanometer resolution. After various RTO treatments (dry and wet oxide) resulting in an ellipsometric measured oxide thickness of 5 nm, the distribution of dopants was analysed by secondary ion mass spectroscopy (SIMS) and compared with standard thermal processes. Metal-oxide-semiconductor structures (MOS-structures) were fabricated for electrical characterisation, It turns out that for a low thermal budget and minimised OED only wet RTO is feasible.(C) 2000 Published by Elsevier Science Ltd. All rights reserved.