Improvement of voltage linearity in high-kappa MIM capacitors using HfO2-SiO2 stacked dielectric

Abstract

It is demonstrated that the voltage coefficients of capacitance (VCC) in high-k, metal-insulator-metal (MIM) capacitors can be actively engineered and voltage linearity can be significantly improved maintaining high capacitance density, by using a stacked insulator structure of high-k and SiO2 dielectrics. A MIM capacitor with capacitance density of 6 fF mum(2) and quadratic VCC of only 14 ppm/V-2 has been demonstrated together with excellent frequency and temperature dependence (temperature coefficients of capacitance of 54 ppm degreesC) as well as low leakage current of less than 10 nA/cm(2) up to 4 V at 125 degreesC.