Electrical and Reliability Analysis for GDH High-k Films After Rapid Thermal Annealing

The amorphous HfO2 doped Gd2O3 (GDH) film has been grown on p-type Si (001) substrates by radio frequency co-sputtering, and the thickness of GDH film was 4.4nm. The results of electrical tests showed that the ΔVFB of C-V curves reduced from 170mV to 40mV, dielectric constant increased from 19.6 to 21.3, and relaxation phenomena decreased after RTA. I-V curves showed that the leakage current density of GDH film was reduced from 9.6×10-4 A/cm2 to 1.3×10-5 A/cm2 after Rapid Thermal Annealing (RTA). The reliability studies on GDH gate dielectric show that the Time Zero Dielectric Breakdown (TZDB) was mainly caused by the accumulation of positive charges.