Effect of interfacial silicon on the structural stability of C54-TiSi2 on SiO2

The formation of interconnect C54-TiSi2 on SiO2 substrates suffers severe s tructural instability upon rapid thermal anneal. To understand the structur al instability from a mechanistic point of view, we investigated the interf acial features of the C54-TiSi2 on SiO2 using Auger electron spectroscopy a nd cross-sectional transmission electron microscopy. As a result, we noted that the surplus silicon layer retained at the interface between the C54-Ti Si2 thin film and the SiO2 substrates is indispensable for the stabilizatio n of the C54-TiSi2 on SiO2. We explained the affirmative role of the silico n layer retained at the interface in terms of the residual stress of the C5 4-TiSi2 thin film. (C) 2000 American Institute of Physics. [S0003-6951(00)0 1325-5].