In this work the influence of Selective Epitaxial Growth (SEG), high-k gate-dielectric and rotation of the channel on the low frequency (LF)-noise is investigated The carrier number fluctuations dominate the 1/f noise for all the devices studied An unusual effective trap density profile is found. It decays with a larger distance from the interface. This implies a higher trap density in the interfacial SOI2-layer, compared with the high-k dielectric The shape of the profile is different for a HfSiON gate-dielectric compared with a HfO2 gate-dielectric Higher trap densities are found for the latter. The Selective Epitaxial Growth (SEG) and channel orientation show only a negligible impact on the noise behavior when a HfSiON-dielectric is used (C) 2009 Elsevier Ltd All rights reserved