Improved electrical properties using SrTiO3/Y2O3 bilayer dielectrics for MIM capacitor applications

In this paper, we show that the capacitance–voltage linearity of MIM structures can be enhanced using SrTiO3 (STO)/Y2O3 dielectric bilayers. The C(V) linearity is significantly improved by combining two dielectric materials with opposite permittivity-voltage responses. Three STO/Y2O3 stacks with different thicknesses were realized and compared to a 20 nm STO single layer structure. We observed that an increase in the Y2O3 thickness leads to an improvement in the voltage linearity, while maintaining an overall capacitance density greater than 10 fF/μm2.