A Highly Reliable MIM Technology with non-Crystallized HfOx Dielectrics Using Novel MOCVD Stacked TiN Bottom Electrodes

Abstract

We have developed a key process technology on HfOx-MIM (Metal-Insulator-Metal) capacitors, which overcomes a crucial issue on incidental TDDB failure. We revealed this failure was induced by the leakage current along the weak path through the micro-crystalline boundary in HfOx films. Novel stacked TiN bottom electrodes, which had amorphous TiN films on the top of crystalline electrodes, were adopted for suppressing the crystallization of the dielectrics. Excellent leakage characteristics below 10fA/cell and TDDB lifetime over 100yrs have been achieved for the concave type HfOx-MIM arrays with Teq of 1.1nm.