abstract |
An integrated capacitor is provided, incorporating a high dielectric constant material. In a disclosed method, a high k capacitor dielectric is formed in the shape of a container above a protective layer. After the dielectric is formed, inner and outer electrodes are formed, representing storage and reference electrodes of a memory cell. Contact is separately made through the protective layer from a storage electrode layer, which lines the inner surface of the dielectric, to an underlying polysilicon plug. The contact can be a thin layer lining the interior of the storage electrode layer, or can completely fill the container capacitor. In the latter instance, the contact can form part of the storage electrode and contribute to capacitance of the cell. Volatile dielectric materials can thus be formed prior to the electrodes, avoiding oxidation of the electrodes and underlying polysilicon plug, while also minimizing oxygen depletion through diffusion from the high dielectric constant material. |