Low pressure chemical vapor deposition ͑LPCVD͒ of silicon nitride from bis͑tertiary-butylamino͒silane ͑BTBAS͒ and ammonia precursors has been demonstrated at 550-600°C in a 200 mm vertical batch furnace system. Deposition rates of 4-30 Å/min are achieved with a film thickness variation below 2% 1-sigma. Silicon nitride depositions using BTBAS and NH 3 were found to retain a significant mass-transfer limiting component at temperatures Ͻ600°C. Substantial carbon and hydrogen incorporation are detected in low-temperature BTBAS silicon nitride, relative to dichlorosilane based silicon nitride deposited at higher temperature. These impurities result in the formation of a SiNCH solid solution with carbon substitution of nitrogen and disproportionate occupation of silicon and nitrogen sites by interstitial hydrogen. Optical and physical properties of silicon nitride are significantly altered by the addition of carbon and hydrogen impurities. Etch resistance of BTBAS-derived silicon nitride was found to diminish at elevated hydrogen levels. However, increasing etch resistance is observed in silicon nitride films with higher carbon levels. The data from this study indicate that carbon and hydrogen impurity concentrations may be tuned to produce silicon nitride with specific material properties.

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