The Transactions of the Korean Institute of Electrical Engineers C (대한전기학회논문지:전기물성ㆍ응용부문C)

The Korean Institute of Electrical Engineers (대한전기학회)
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Chemical Mechanical Polishing (CMP) Characteristics of BST Ferroelectric Film by Sol-Gel Method

졸겔법에 의해 제작된 강유전체 BST막의 기계.화학적인 연마 특성

  • 서용진 (대불대학교 전기공학과) ;
  • 박성우 (대불대학교 전기공학과)
  • Published : 2004.03.01
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Abstract

The perovskite ferroelectric materials of the PZT, SBT and BST series will attract much attention for application to ULSI devices. Among these materials, the BST ($Ba_0.6$$Sr_0.4$/$TiO_3$) is widely considered the most promising for use as an insulator in the capacitors of DRAMS beyond 1 Gbit and high density FRAMS. Especially, BST thin films have a good thermal-chemical stability, insulating effect and variety of Phases. However, BST thin films have problems of the aging effect and mismatch between the BST thin film and electrode. Also, due to the high defect density and surface roughness at grain boundarys and in the grains, which degrades the device performances. In order to overcome these weakness, we first applied the chemical mechanical polishing (CMP) process to the polishing of ferroelectric film in order to obtain a good planarity of electrode/ferroelectric film interface. BST ferroelectric film was fabricated by the sol-gel method. And then, we compared the surface characteristics before and after CMP process of BST films. We expect that our results will be useful promise of global planarization for FRAM application in the near future.

Keywords

References

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