Improved electrical characteristics and reliability of Ge MOSFET device with nitrided high-k gate dielectric by plasma immersion ion implantation

摘要

MOSFET devices with Ge channel and nitridation treatment using plasma immersion ion implantation (PHI) are studied in this work. Experimental results show that the electrical characteristics and reliability of Ge MOSFETs can be significantly improved by PHI nitridation. For instance, the mobility of device with 3 nm Si cap after PHI nitridation is enhanced by about 20%. Although the driving drain current of sample with a thinner Si cap is higher, its reliability property is worse. Regarding the effects of energy in PHI nitridation, the electrical characteristics of the sample with 2 keV are better than that with 1.5 keV.