Demonstration and characterization of 500 V MIM capacitor with Al2O3 dielectric layer for power integrated circuits

Abstract

In this work, the metal–insulator–metal (MIM) capacitor with Al2O3 dielectric layer above 1 μm and TiN electrodes has been fabricated by magnetron sputtering for power integrated circuits application. The characteristics of the TiN and Al2O3 films were inspected by scanning electron microscopy (SEM), transmission electron microscopy (TEM) and energy-dispersive X-ray spectroscopy (EDS) technologies. According to the experimental results, the fabricated MIM capacitor exhibits a very low leakage current density of 4.2×10-5 A/cm2 at 500 V, although the capacitance density is relatively small (0.08 fF/μm2at 100 kHz) due to its high voltage withstanding capability. In addition, the quadratic and linear voltage coefficients of the capacitor are 0.08 ppm/V2and −2.39 ppm/V, respectively (at 100 kHz), indicating its excellent voltage linearity. Leakage mechanisms of the capacitor have been investigated as well. As a result, the fabricated Al2O3 MIM capacitor is a very promising candidate for power integrated circuits application.