Impact of Mobility Boosters (XsSOI, CESL, TiN gate) on the Performance of ≪100≫ or ≪110≫ oriented FDSOI cMOSFETs for the 32nm Node

For the first time, we integrated 1.9 GPa eXtra-strained silicon on insulator (XsSOI) substrates in FDSOI n and pMOSFETs with gate length (L_G) and width (W) down to 25 nm. Due to the high stress levels, significant I_ON-I_OFF improvements were obtained not only for nMOS but also for pMOS. We compared those results with the performance of devices strained by contact etch stop layer (CESL), for different device orientations (<110> or <100>) and feature sizes (L_G, W). We demonstrate that, similarly to XsSOI, a single tensile CESL can improve both n and pMOS performance, leading to I_ON,n=700 muA/mum and I_ON,p=430 muA/mum at I_OFF=140 pA/mum, this for L_G<35 nm, W=50 nm and V_DD=1 V along the <100> direction.