Method for manufacturimg a SOI wafer

摘要

This invention relates to a method of fabricating a SOI (Silicon-On-Insulator) wafer suitable to manufacture electronic semiconductor devices and including a substrate of monocrystalline silicon with a top surface, and a doped buried region in the substrate. The method comprises at least one step of forming trench-like openings extended from the substrate surface down to the buried region, and comprises: a selective etching step carried out through said openings to change said buried region of monocrystalline silicon into porous silicon; a subsequent step of oxidising the buried region that has been changed into porous silicon, to obtain an insulating portion of said SOI wafer.