Chemical Mechanical Polishing Characteristics of BTO Thin Film for Vertical Sidewall Patterning of High-Density Memory Capacitor

고집적 메모리 커패시터의 Vertical Sidewall Patterning을 위한 BTO 박막의 CMP 특성

  • Published : 2006.03.01

Abstract

Most high-k materials are well known not to be etched easily, Some problems such as low etch rate poor sidewall angle, plasma damage, and process complexity were emerged from the high-density DRAM fabrication. Chemical mechanical polishing (CMP) by a damascene process was proposed to pattern this high-k material was polished with some commercial silica slurry as a function of pH variation. Sufficient removal rate with adequate selectivity to realize the pattern mask of tera-ethyl ortho-silicate (TEOS) film for the vertical sidewall angle were obtained. The changes of X-ray diffraction pattern and dielectric constant by CMP process were negligible. The planarization was also achieved for the subsequent multi-level processes. Our new CMP approach will provide a guideline for effective patterning of high-k material by CMP technique.

Keywords

References

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