Abstract: A platinum deposition method uses a combination of an oxide adhesion layer and a high temperature thin film deposition process to produce platinum bottom electrodes for ferroelectric capacitors. The platinum bottom electrode is deposited onto a TiOx layer at temperatures between about 300 and 800° C. Deposition at high temperatures changes the platinum stress from compressive to tensile, increases platinum grain size, and provides a more thermally stable substrate for subsequent PZT deposition.

Abstract: A method for fabricating integrated capacitors, of particular utility in forming a ferroelectric capacitor array for a ferroelectric memory integrated circuits, begins with provision of a substrate. The substrate is typically a partially-processed CMOS integrated circuit wafer coated with an adhesion layer. Upon the substrate is deposited a bottom electrode layer, typically of noble metal, a dielectric layer, typically doped PZT, and a top electrode layer, typically a noble metal oxide. Next is deposited a hardmask layer of strontium ruthenium oxide, followed by a photoresist layer. The photoresist layer is aligned, exposed, developed, and cured as known in the art of integrated circuit photolithography. The resulting stack is then dry etched to remove undesired portions of the hardmask layer, the top electrode layer, and the dielectric layer. A principle advantage of the process is that a single photomasking operation is sufficient to define the top electrode and dielectric layers.