고유전율막의 CMP 특성

Chemical Mechanical Polishing Characteristics of High-k Thin Film

In this paper, we first applied the chemical mechanical polishing (CMP) process to the planarization of ferroelectric film in order to obtain a good planarity of electrode/ferroelectric film interface. BST ($Ba_{0.6}Sr_{0.4}TiO_3$), PZT ($Pb_{1.1}(Zr_{0.52}TiO_{0.48})O_3$) and BTO ($BaTiO_3$) ferroelectric film are fabricated by the sol-gel method. And then, we compared the structural characteristics before and after CMP process of BST, PZT, BTO films. Their dependence on slurry composition was also investigated. We expect that our results will be useful promise of global planarization for ferroelectric random access memories (FRAM) application in the near future.