Patent ID: 6617626
Filing Date: 2003-09-09
Classification: H01L

Abstract:
A ferroelectric random access memory, comprising:a substrate carrying thereon an active device; a lower electrode provided over said substrate in electrical connection with said active layer; a ferroelectric film containing at least Pb, Zr and Ti and having a perovskite structure, said ferroelectric film comprising a number of crystal grains extending continuously from a bottom surface to a top surface of said ferroelectric film and forming a columnar microstructure, said crystal grains having pinholes; and an upper electrode of a conductive oxide film provided on said ferroelectric film, said upper electrode having a perovskite structure and containing therein Sr and Ru, said ferroelectric film further containing Ca and Sr, said ferroelectric film including said pinholes with a density not exceeding 34 pinholes/&mgr;m2.