sSOI relaxation by BOX creep technique for dual strain CMOS integration

We report here on sSOI (strained Silicon On Insulator) strain relaxation at a local scale using a simple process based on BOX creep. This method consists in the transfer of SiN strain to a thin silicon layer during a high temperature anneal. This is allowed by the creep of the Buried Oxide (BOX). Thanks to Raman spectroscopy, the induced relaxation in the Si layer is determined. Using a tensile stressed SiN on + 1.4 GPa sSOI, we obtain around 60 % of strain relaxation.