Conducting diffusion barriers for integration of ferroelectric capacitors on Si

Abstract We present in this article a review of the various approaches to integrate thin film Pb(Zr, Ti)O3-based ferroelectric capacitor structures on a filled poly-Si plug, which is a critical requirement for a high-density memory technology. Key materials issues relevant to the development of conducting diffusion barrier layers for integration of these materials on Si wafers are discussed. Specific attention in this paper is on the use of conducting perovskite oxide electrodes to contact the ferroelectric thin film. The second part of this review focuses on some novel materials that we have investigated for use as diffusion barriers. The principal advantage is that this barrier layer eliminates the use of Pt or Ir, thereby discarding any etching and cost issues associated with the noble materials.