Electrical Characterization of Metal–Insulator–Metal Capacitors with Atomic-Layer-Deposited HfO ₂ Dielectrics for Radio Frequency Integrated Circuit Application

Abstract

Metal–insulator–metal (MIM) capacitors with atomic-layer-deposited HfO2 dielectric and TaN electrodes are investigated for rf integrated circuit applications. For 12 nm HfO2, the fabricated capacitor exhibits a high capacitance density of 15.5 fF/μm2 at 100 kHz, a small leakage current density of 6.4×10−9 A/cm2 at 1.8 V and 125°C, a breakdown electric field of 2.6 MV/cm as well as voltage coefficients of capacitance (VCCs) of 2110 ppm/V2 and -824 ppm/V at 100 kHz. Further, it is deduced that the conduction mechanism in the high field range is dominated by the Poole–Frenkel emission, and the conduction mechanism in the low field range is possibly related to trap-assisted tunnelling. Finally, comparison of various HfO2 MIM capacitors is present, suggesting that the present MIM capacitor is a promising candidate for future rf integrated circuit application.