The present invention is related to the realization of a simplified bottom
electrode stack for ferroelectric memory cells. More particularly, the
invention is related to ferroelectric memory cells wherein the
ferroelectric capacitor is positioned directly on top of a contact plug.
The bottom electrode stack is prepared by depositing a ferroelectric film
atop an Ir or Ru metal electrode layer, then annealing the ferroelectric
layer in an oxygen ambient wherein the partial pressure of oxygen is
controlled at a level sufficient to oxidize the ferroelectric layer but
not at a level sufficient to oxidize the metal electrode layer.