Abstract
An interfacial SiO2 hampers a silicidation reaction between Co and Si. A refractory metal cap is believed to block ambient oxygen diffusing toward the Co/Si interface. However, an interfacial SiO2 can also be present prior to and/or during the annealing. This work reports on our findings of the interaction between SiO2 and Co layers capped with refractory metals. It was found that Ti diffuses through the Co layer and segregates underneath the Co, which leads to the reduction of SiO2 and the formation of free Si. The free Si in-diffuses and reaches the original Ti surface. On the other hand, TiN shows a very inert behavior compared to Ti. The results are discussed in connection with Co silicidation processes.
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Kondoh, E., Conard, T., Brijs, B. et al. A chemical role of refractory metal caps in Co silicidation: Evidence of SiO2 reduction by Ti cap. Journal of Materials Research 14, 4402–4408 (1999). https://doi.org/10.1557/JMR.1999.0595
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DOI: https://doi.org/10.1557/JMR.1999.0595