Abstract
In order to cater to the current direction of development of CMOS devices, in this paper, we propose two possible ways to improve device performance. In the first topic, we use rare earth oxides Yb2O3 combine with high dielectric constant crystalline materials ZrTiO4 as the gate dielectric to fabricate n- MOSFETs.Electrical characteristics show that the device has low EOT under 1nm, good subthreshold behavior, excellent high field mobility and small amount of interface trap density all indicate that the surface quality between Si and Yb2O3 is very promising. In the second topic, the rare earth oxides Sm2O3 was proposed as the gate dielectric to fabricate Ge MOSCAPs. Electrical characteristics show that the device has low EOT, reasonable leakage current value, and small amount of interface trap density, suggest that the Ge surface was effective passivated by Sm2O3. Based on the above results, we can conclude that using rare earth oxides Yb2O3 and Sm2O3 as the gate dielectric for both Si-MOSFET and Ge-MOSCAP have considerable potential.