반도체디스플레이기술학회지 (Journal of the Semiconductor & Display Technology)

한국반도체디스플레이기술학회 (The Korean Society Of Semiconductor & Display Technology)
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수직하중에 의한 응력이 CMP 공정의 디싱에 미치는 영향

Investigation of the Relationship Between Dishing and Mechanical Stress During CMP Process

  • 김형구 (전북대학교 기계설계공학부) ;
  • 김승현 (전북대학교 기계설계공학부) ;
  • 김민우 (전북대학교 대학원 기계설계공학과) ;
  • 임익태 (전북대학교 기계설계공학부)
  • Hyeong Gu Kim (Dept. of Mechanical Design Engineering, College of Engineering, Jeonbuk National Univ.) ;
  • Seung Hyun Kim (Dept. of Mechanical Design Engineering, College of Engineering, Jeonbuk National Univ.) ;
  • Min Woo Kim (Dept. of Mechanical Design Engineering, Graduate School, Jeonbuk National Univ.) ;
  • Ik-Tae Im (Dept. of Mechanical Design Engineering, College of Engineering, Jeonbuk National Univ.)
  • 투고 : 2023.05.09
  • 심사 : 2023.06.21
  • 발행 : 2023.06.30
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초록

Since dishing in the CMP process is a major factor that hinders the uniformity of the semiconductor thin film, many studies have focused this issue to improve the non-uniformity of the film due to dishing. In the metal layer, the dishing mainly occurs in the central part of the metal due to a difference in a selection ratio between the metal and the dielectric, thereby generating a step on the surface of the metal layer. Factors that cause dishing include the shape of the thin film, the chemical reaction of the slurry, thermal deformation, and the rotational speed of the pad and head, and dishing occurs due to complex interactions between them. This study analyzed the stress generated on the metal layer surface in the CMP process using ANSYS software, a commercial structure analysis program. The stress caused by the vertical load applied from the pad was analyzed by changing the area density and line width of the dummy metal. As a result of the analysis, the stress in the active region decreased as the pattern density and line width of the dummy metal increased, and it was verified that it was valid compared with the previous study that studied the dishing according to the dummy pattern density and line width of the metal layer. In conclusion, it was confirmed that there is a relationship between dishing and normal stress.

키워드

참고문헌

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