An original technique is used to induce a compressive strain in the channel of Fully Depleted (FD)SOI MOSFETs thanks to an embedded buried nitride stressor. Strain measurements are performed by Grazing Incidence X-ray Diffraction (GIXRD) and compared to mechanical simulations. Both results are in agreement and prove that the strain level can achieve -0.6 % (-780 MPa) in the channel of a transistor, depending on the active region geometry and the nitride properties (intrinsic strain and thickness). This technique is thus very promising in order to boost pMOSFETs on thin films.