Method for manufacturing a finfet MOS transistor

摘要

The method involves forming a trench delimiting a semiconductor fin (107) in a semiconductor layer (101) from a surface of the semiconductor layer and extending all the way to a surface of semiconductor support (105). Sides of a portion of a silicon oxide layer (103) located under the fin is etched to form a recess under the fin. The recess is filled with a material e.g. nitride, selectively etchable over silicon oxide, where the material has a greater dielectric constant than silicon oxide. The trench is extended all the way to an intermediate level of the support. An independent claim is also included for a metal oxide semiconductor (MOS) transistor formed from a semiconductor on insulator (SOI)-type structure.