Investigation on the electric properties of Bi1.5ZnNb1.5O7 thin films grown on TiN substrate for MIM capacitors

Abstract

A small crystalline phase was formed in the Bi1.5ZnNb1.5O7 (BZN) film grown at 300 degrees C on TiN/SiO2/Si substrate using RF-magnetron sputtering. A 46-nm-thick BZN film exhibited a high capacitance density of 13.6 fF /mu m(2) at 100 kHz with a dielectric constant of 71, which did not change even in the gigahertz range (1-6 GHz). The quality factor was high, approximately 50, at 2.5 GHz. The leakage-current density was low, approximately 5.66 nA/cm(2), at 2 V. The quadratic voltage and temperature coefficients of capacitance were approximately 631 ppm/V-2 and 149 ppm/degrees C at 100 kHz, respectively. These results indicate that the BZN film grown on TiN substrate at 300 degrees C can be a good candidate material for metal-insulator-metal capacitors.