The HfTiO/Y2O3 stacked dielectric is proposed as the dielectric of metal-insulator-metal (MIM) capacitor. Y2O3 is more thermodynamically stable than HfTiO as contacting with TaN electrode. Interfacial layer thickness and leakage current density can be reduced by inserting a thin Y2O3 layer between HfTiO and TaN. The negative quadruple voltage coefficient of capacitance (VCC-α) of Y 2O3 cancels out the positive VCC-α of HfTiO to achieve low VCC-α. The MIM capacitor structure with HfTiO/Y 2O3 dielectric shows a capacitance density that is higher than 11 fF/μ2 and VCC-α that is lower than 1222 ppm/V 2. The leakage currents at.1 and.2 V are 6.4 and 14 nA/cm 2, respectively. These results suggest that the HfTiO/Y 2O3 stacked dielectric is a promising candidate for MIM capacitors.
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