Channel Hot-Carrier degradation in short channel devices with high-k/metal gate stacks

Channel Hot-Carrier (CHC) degradation in short channel transistors with a high-k/metal gate stack processed in CMOS technology has been analysed. For short channel transistors (L≪0.15¿m), the most damaging stress condition has been found to be VG=VD instead of the "classical" VG=VD/2 determined for long channel transistors. In this work, we have demonstrated that this shift is not caused by the presence of the high-k layer but due to short channel effects. Furthermore, the CHC degradation lifetime has been evaluated, revealing larger operating voltages for high-k than for SiO2 based transistors.