Width and orientation effects in strained FDSOI MOSFETs: strain and device characterization

We integrated Fully Depleted Silicon-On-Insulator (FDSOI) n and pMOSFETs on (1.16 percent, 2.1GPa) eXtremely strained SOI (XsSOI) substrates. We demonstrate a 135% electron mobility enhancement at W=77nm and a significant I ON -I OFF improvement for short and narrow nMOS on XsSOI compared to unstrained SOI. We in-depth analyze this performance boost thanks to accurate extractions in narrow devices of both the carrier mobility (after adaptation of the split-CV method) and the strain (by X-Ray Diffraction performed in synchrotron facility). This improvement depends on the channel orientation and is partly attributed to the tensile strain induced by the TiN gate and partly by the effective mass improvement under high and non-biaxial strain.