Improved Lower Electrode Oxidation of High-kappa TiCeO Metal-Insulator-Metal Capacitors by Using a Novel Plasma Treatment

Abstract

We have fabricated high-kappa Ir/TiCeO/TaN metal-insulator-metal (MIM) capacitors using a dual plasma treatment on bottom electrode. The novel plasma treatment suppresses the growth of bottom interfacial layer to reduce the degradation of capacitor performance under 400 degrees C PDA. A low leakage current of 1.7x10(-7) A/cm(2) at -1 V and capacitance density of similar to 18 fF/mu m(2) at 1 MHz were obtained for 21 nm thick TiCeO MIM devices; moreover, a 37 nn thick TiCeO film has a capacitance density of 11 fF/mu m(2), which gives a kappa value of 45. Consequently, the excellent device performance is due to the combined effects of the dual plasma treatment, high-kappa TiCeO dielectric and a high work-function Ir metal.