Reliability study of methods to suppress boron transient enhanced diffusion in high-k/metal gate Si/SiGe channel pMOSFETs

The effects of extension profile engineering to suppress boron transient enhanced diffusion (TED) are investigated in Si/SiGe channel metal-oxide-semiconductor field-effect transistor (MOSFET). In performance, Ge pre-amorphization implantation (PAI) samples exhibit low drain-induced barrier lowering (DIBL) and a good Ion/Ioff ratio due to suppressed boron diffusion. In reliability, negative bias temperature instability (NBTI) degradation is reduced in Si/SiGe channel pMOSFETs, but hot carrier injection (HCI) degradation is worsened, especially in Ge PAI samples. The results suggest that HCI is an important factor in limiting device life time in Si/SiGe channel pMOSFETs.