Scaling potential and MOSFET integration of thermally stable Gd silicate dielectrics

We investigate the potential of gadolinium silicate (GdSiO) as a thermally stable high-k gate dielectric in a gate first integration scheme. There silicon diffuses into gadolinium oxide (Gd2O3) from a silicon oxide (SiO2) interlayer specifically prepared for this purpose. We report on the scaling potential based on detailed material analysis. Gate leakage current densities and EOT values are compatible with an ITRS requirement for low stand by power (LSTP). The applicability of this GdSiO process is demonstrated by fully functional silicon on insulator (SOI) metal oxide semiconductor field effect transistors (MOSFETs).