Effects of substrate bias and temperature during titanium sputter-deposition on the phase formation in TiSi2

The formation of titanium disilicide (TiSi2) from Ti deposited using ionized metal plasma under different deposition conditions has been investigated. It is shown that deposition at elevated substrate temperature (450°C) enhances the formation of the low-resistivity C54 TiSi2, especially in patterned narrow lines. Grain-boundary footprint pictures obtained by atomic force microscopy indicate a larger grain-size distribution for the films deposited at higher substrate temperature. Deposition under substrate bias resulted in reduced contact resistivity. However, the use of substrate bias results in increased probability of bridging of silicide over the isolating spacers.