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Summary form only given. High-density, embedded ferroelectric memory (FeRAM) has the potential to replace embedded flash, embedded DRAM, and non-cache SRAM and could be a key enabler for future system-on-a-chip applications. Despite this appeal, the evidence that ferroelectric capacitors can be scaled to the submicron regime has been limited. In this paper, we report the fabrication and electrical properties of submicron PZT capacitors formed using both planar bottom electrodes and W plug contact structures. We observe that the aggregate saturation polarization value is nearly independent of individual capacitor area in the measured range from the contact-limited size of 0.12 /spl mu/m/sup 2/ to 10/sup 4/ /spl mu/m/sup 2/. This result suggests that high-density, embedded FeRAM technology may be feasible.

A unique, single-step damascene approach was used to form ferroelectric capacitors with noble metal electrodes. In this study an oxidized Si substrate was coated with a blanket W film and a patterned SiO/sub 2/ film. Capacitors were formed by conformal deposition of a sputtered bottom electrode structure (100 nm Ir/50 nm TiAlN), MOCVD ferroelectric (130 nm (Pb,Ca)ZrTiO/sub 3/), and sputtered top electrode (150 nm Ir). A halide-based slurry was used in a single multi-layer polish to define planar, recessed capacitors between 100/spl times/100 /spl mu/m/sup 2/ and 10/spl times/10 /spl mu/m/sup 2/. The Ir removal rate was 14 nm/minute. Annealed capacitors had ferroelectric and dielectric properties that were similar to conventionally processed capacitors. 2P/sub r/ and switched charge at 2V were found to be 42 /spl mu/C/cm/sup 2/ and 40 /spl mu/C/cm/sup 2/ respectively with a leakage current density of 10/sup -4/ A/cm/sup 2/ at 2V.