Strained FDSOI CMOS technology scalability down to 2.5nm film thickness and 18nm gate length with a TiN/HfO2 gate stack
Résumé
Scalability of both unstrained and strained FDSOI CMOSFETs is explored for the first time down to 2.5nm film thickness and 18nm gate length with HfO2/TiN gate stack. Off-state currents in the pA/mu m range are achieved for 18nm short and 3.8nm thin MOSFETs thanks to outstanding electrostatic control: 67mV/dec subthreshold swing and 75mV/V DIBL. For such thin bodies, the buried oxide fringing field limitation on DIBL is experimentally evidenced and quantified for the first time. Furthermore, we demonstrate strain induced ION gain as high as 40% on the shortest transistors. An in-depth analysis of this gain as a function of the film thickness is carried out through mobility and ballisticity extractions.