Electrodes and Barriers for DRAM and FERAM: Processing, Integration, and Fundamentals

Materials requirements for electrodes and barriers in high density dynamic random access memory (DRAM) and ferroelectric random access memory (FERAM) are reviewed, and some approaches to barrier materials and device geometries are described. Electrode/barrier topics covered in more detail include Pt reactivity with Si-containing barriers and dielectric overlayers, the application of a Bragg-Brentano x-ray diffraction technique to quantitatively probe Pt and Ir electrode morphology and thickness changes during ferroelectric processing, the stability of metal oxide electrode materials in reducing ambients, electrode patterning techniques (including Pt electroplating), and electrical properties of 3-D capacitors in 256k arrays as a function of top electrode annealing treatments.