Image Number 5 for United States Patent #7943474.
A method for forming a memory device is provided by first forming at least one trench in a semiconductor substrate. Next, a lower electrode is formed in the at least one trench, and thereafter a conformal dielectric layer is formed on the lower electrode. An upper electrode is then formed on the conformal dielectric layer. The forming of the upper electrode may include a conformal deposition of metal nitride layer, and a non-conformal deposition of an electrically conductive material atop the metal nitride layer, in which the electrically conductive material encloses the at least one trench.