| Title |
Chemical Mechanical Polishing Characteristics of BTO Thin Film for Vertical Sidewall Patterning of High-Density Memory Capacitor |
| Authors |
고필주(Ko, Pil-Ju) ; 박성우(Park, Sung-Woo) ; 이강연(Lee, Kang-Yeon) ; 이우선(Lee, Woo-Sun) ; 서용진(Seo, Yong-Jin) |
| Keywords |
CMP(Chemical Mechanical Polishing) ; BTO(BaTiO_3) ; Sidewall Angle ; Consumables ; Damascene pH (Potential of Hydrogen) ; TEOS(Tera-Ethyl Ortho-Silicate) |
| 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. |