The impact of the front oxide quality on the performance of SOI devices is investigated. In this respect, a Fowler-Nordheim stress is performed for both partially (PD) and fully (FD) depleted N-MOSFETs. Various special SOI mechanisms are analyzed, as floating body effects for PD devices and coupling effects, between front and back interfaces, for FD ones. In the first part, the influence of the front oxide quality in PD transistors on transient effects and low-frequency noise (LFN), which both are influenced by the floating body, is analyzed. In the second part, the impact of the front oxide and coupling effects on the LFN in FD MOSFETs is investigated. (C) 2002 Published by Elsevier Science Ltd.