Interaction of a Ti-capped Co thin film with Si3N4

The reaction of a Ti (8 nm) capped Co film (15 nm) with a Si3N4 layer (150 nm) is studied after rapid thermal annealing at 660 degreesC for 120 s in a N-2 ambient. X-ray photoelectron spectroscopy, transmission electron micro scopy, electron energy-loss spectroscopy, and Auger electron spectroscopy a re used to study the reaction products. Combining the results of the differ ent analyses yields a layer stack consisting of: TiO2/TiO/unreacted Co/(Ti, Co)(2)N/Co2Si, followed by amorphous Si3N4. The reaction mechanisms are dis cussed. Conclusions concerning the risk for degradation of nitride spacers in advanced devices are drawn. (C) 2000 American Institute of Physics. [S00 03-6951(00)05248-7].