A Study on the Characteristics change of WSix Thin Films by S/H Life Time

S/H Life Time에 따른 WSix의 특성 변화에 관한 연구

  • 정양희 (여수대학교 전기공학과) ;
  • 강성준 (여수대학교 반도체응용물리학과)
  • Published : 2002.08.01

Abstract

Film compositions are needed in semiconductor manufacturing for such diverse application as production tool qualifications and process development. Surface and interface information is generally provided with Auger electron spectroscopy(AES). In this paper, WSix films were analyzed for structural, electrical, and compositional properties of tungsten silicide thin films produced by low pressure chemical vapor deposition as a function of temperature, DCS post flow, shower head life time, and the silicon to tungsten ratios have been investigated. We find that Si/W composition ratio is increased in the surface and interface of WSix thin films by the DCS post flow process and increasing deposition temperature, respectively. The results obtained in this study are also applicable to process control of WSix deposition for memory device fabrication.

막질의 조성은 공정 개발과 고품질 생산 적용을 위한 반도체 소자의 제조에 있어서 풍요한 요소의 하나 이다. 막의 표면과 계면의 조성은 기본적으로 AES측 통하여 알 수 있다. 본 연구에서는 온도, DCS post flow, shower head life time 등과 같은 공정조건으로 LPCVD법을 이용한 tungsten suicide 박막을 증착하고 이들의 구조적, 전기적 특성과 조성비를 측정하며 WSix박막을 해석하였고 이로부터 Si/W의 조성비를 비교하였다. Si와 W의 조성비는 DCS post flow에 의하여 WSix박막의 표면에서 증가하였으며, 폴리실리콘과 tungsten silicide 계면에서는 온도의 증가에 따라 조성비가 증가함을 알 수 있었다. 이 결과는 메모리 소자 제조의 WSix 박막 증착의 공정조건 최적화에 적용될 수 있다.

Keywords

References

  1. S. Santucci, L. Lozzi, M. Passacantando, and P. Picozzi 'Studies on structural, electrical, compositional, and mechanical properties of WSix thin films produced by low-pressure chemical vapor deposition' J. Vac. Sci. Technol. A 16(3), pp. 1207-1212, 1998 https://doi.org/10.1116/1.570191
  2. K. M. Chang, I. C. Deng 'Barrier characteristics of chemical vapor deposition amorphous-like tungsten silicide with in situ nitrogen plasma treatment' J. of the electrochem Soc. 146(7) pp. 2533-2539, 1999 https://doi.org/10.1149/1.1391967
  3. C. A. Bradbury and D. K. Fillmore 'Tungsten silicide composition analysis by Rutherford backscattering spectroscopy, Auger electron spectroscopy, and x-ray photoelectron spectroscopy' J. Vac. Sci. Technol. A 16(3), pp. 1103-1105, 1998 https://doi.org/10.1116/1.581240
  4. K. Roh, S. Youn, and Y. Roh 'Tungsten silicide for the alternate gate metal in metal-oxide-semiconductor devices' J. Vac. Sci. Technol. A 19(4), pp. 1562-1565, 2001 https://doi.org/10.1116/1.1345914
  5. S. F. Lin, C. H. On, S. Lee, Y. C. Tien, and C. F. Hsu 'Investigation of the time-delay effect on the critical dimension of tungsten silicide/polysilicon gate after reactive ion etching' Proceedings of the international symp. plasma etching processes for sub-quarter micron devices, pp. 186-192, 1999
  6. J. S. Byun, B. H. Lee, J. S. Park, D. K. Sohn, J. G. Hong, W. J. Cho, S. J. Choi, and J. J. Kim 'Reduction of Dichlorosiliane- Based Tungsten Silicide Resistivity by Amorphization and its Appilicability as an Electrode' J. of the Electrochem. Soc. Vol. 146, No. 6., pp. 2261-2269, 1999 https://doi.org/10.1149/1.1391925
  7. J. S. Byun, B. H. Lee, J. S. Park, D. K. Sohn, S. J. Choi, and J. J. Kim 'Formation of high Conductivity WSix Layer and its Characterization as a gate Electrode' J. Electro chem. Soc., Vol. 145, No. 9, pp. 3228-3235, 1998 https://doi.org/10.1149/1.1838790
  8. J. G. Lee, S. H. Oh, J. M. Lee, E. G. Lee, I. G. Lim, W. K. Park, and G. H. Kim 'High temperature cracking of tungsten polycide films on quartz sunstrate ' Thin solid films, vol. 370, No. 1-2., pp. 307-310, 2000 https://doi.org/10.1016/S0040-6090(00)00936-6