Impact of Si substrate orientations on electrical properties of crystalline Gd_2O_3 thin films for high-K application

摘要

The authors compare the properties of epitaxial Gd_2O_3 thin films grown on silicon substrates with three different orientations for high-K application. Pt/Gd_2O_3/Si(111) and Pt/Gd_2O_3/Si(110) metal oxide semiconductor heterostructures show promising electrical properties and hence, could be considered for future generation of complementary metal oxide semiconductor devices. Capacitance equivalent oxide thicknesses estimated from capacitance versus voltage characteristics are 0.97, 1.12, and 0.93 nm for the films grown on Si(001), Si(111), and Si(110) substrates, respectively. The films exhibit good insulating property with leakage current densities of 0.4, 0.5, and 4.5 mA/cm~2, respectively, at (V_g-V_(FBV)) = -1 V.