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A Study on the Evaluation of Oxidation Resistance of Nitride Films in DRAM Capacitors

DRAM 커패시터의 질화막 내산화성 평가에 관한 연구

  • 정윤근 (전남대학교 기계설계공학부) ;
  • 강성준 (전남대학교 전기및반도체공학과) ;
  • 정양희 (전남대학교 전기및반도체공학과)
  • Received : 2021.03.17
  • Accepted : 2021.06.17
  • Published : 2021.06.30

Abstract

In order to improve the cell capacitance and scale down in capacitors of semiconductor memory devices, a stacked ONO structure has been introduced as a dielectric layer and thinning of these layers has been attempted continuously. However, many problems have emerged in the manufacturing process. In this study, L/L LPCVD system was used to suppress the growth of natural oxide film of about 10 Å, which was able to secure the capacitance of 3fF / cell. In addition, we investigated the effect of thinning of the dielectric film on the abnormal oxidation of the nitride film, and proposed a stable process control method for forming the dielectric film to ensure oxidation resistance.

반도체 메모리 소자의 커패시터에서 셀 커패시턴스의 향상과 scale down을 위해 유전막으로써 적층형 ONO 구조가 도입되었고 이들의 박막화가 지속적으로 시도되고 있으나 공정 처리 과정에서 많은 문제들이 대두되고 있다. 본 연구에서는 L/L LPCVD를 사용하여 약 10Å의 자연산화막 성장을 억제함으로써 3fF/cell의 정전 용량을 확보할 수 있었다. 또한 유전막의 박막화에 따른 질화막의 이상산화에 미치는 영향을 고찰함으로써 내산화성을 확보할 수 있는 유전막 형성의 안정적인 공정 관리 방법을 제안하였다.

Keywords

References

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