Characteristic Study of Silicon Nitride Films Deposited by LPCVD and PECVD
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This paper analyzes and compares the characteristics of silicon nitride films deposited by low pressure chemical vapor deposition (LPCVD) and plasma enhanced chemical vapor deposition (PECVD), with special attention to the hydrogenation and chemical composition of silicon nitride films. Three different LPCVD processes at various DCS and NH3 gas flow rates and deposition temperatures, together with PECVD using SiH4 and NH3 and ICP CVD using SiH4 and N2, were compared. The silicon nitride film deposition rate decreases with an increasing NH3/DCS ratio in LPCVD, which also leads to an increase in the refractive index and a decrease in the residual stress in the film. There is nearly no hydrogen incorporated in the LPCVD films, which differs from PECVD and ICP CVD that show significant Si-H and N-H bonds. The chemical composition of silicon nitride films is mostly Si-rich, except for the LPCVD process at high NH3/DCS ratio with near stoichiometric chemistry.
KeywordsSilicon nitride films Stress FTIR XPS Binding energy
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This work was performed at the Institute for Electronics and Nanotechnology (IEN) cleanroom at Georgia Institute of Technology, a member of the National Nanotechnology Infrastructure Network, which is supported by NSF Grant No. ECCS-03-35765. The authors would like to acknowledge Mr. Gary Spinner and Claude Roney for their assistance and insightful discussions.
- 14.Machenzie KD, Johnson DJ, DeVre MW, Westerman RJ, Reelfs BH (2005) Stress control of Si-based PECVD dielectrics. In: Proc. of 207th Electrochemical Society Meeting, Quebec, Canada, pp 148–159Google Scholar