High density metal-insulator-metal capacitor based on ZrO2∕Al2O3∕ZrO2 laminate dielectric

Abstract

The metal-insulator-metal (MIM) capacitor for analog and rf applications has been developed with ZrO2∕Al2O3∕ZrO2 laminate as the dielectric. The high capacitance density of 21.54fF∕μm2 can be achieved due to the tetragonal ZrO2 which makes the higher dielectric constant of 38.7. This MIM capacitor also demonstrates the quadratic voltage coefficient of 2443ppm∕V2 and the good leakage current of 2.11×10−6A∕cm2 at 2V which is ascribed to the inserted Al2O3. Since the Schottky emission is suggested as the major dielectric conduction mechanism, a further reduced quadratic voltage coefficient and leakage characteristic can be realized by using a high work-function electrode. The combination of the promising electrical properties and the desirable process integration renders this structure highly suitable for advanced MIM capacitors.