Metal-insulator-metal capacitors using atomic-layer-deposited Al2O3/HfO2/Al2O3 sandwiched dielectrics for wireless communications

摘要

High density metal-insulator-metal (MIM) capacitors are required for radio frequency and analog/mixed-signal integration circuit applications. In this article, high permittivity Al2O3/HfO2/Al2O3 (AHA) dielectrics have been evaluated in comparison with HfO2 using atomic layer deposition technique for MIM capacitor applications. The results indicate that the AHA dielectrics exhibit electrical performance superior to the HfO2 dielectric while retaining similar capacitance density. With respect to 2 nm individual Al2O3 barriers, the MIM capacitor can offer a capacitance density of 2.6 fF/mu m(2), voltage coefficients of capacitance of 71 ppM/V-2 and 9 ppm/V, a leakage current as low as 3 X 10(-9) A/cm(2) at 1 MV/cm and 125 degrees C, an operating voltage- of around 3 V for a ten-year lifetime at 125 degrees C in terms of 50% failure. (c) 2006 American Vacuum Society.