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Low-Energy Electron Microscopy Studies of Interlayer Mass Transport Kinetics on TiN(111)

S. Kodambaka·Navot Israeli·J. Bareno·W. Swiech·Kenji Ohmori·I. Petrov·J. E. Greene
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Abstract

In situ low-energy electron microscopy was used to study interlayer mass transport kinetics during annealing of three-dimensional (3D) TiN(111) mounds, consisting of stacked 2D islands, at temperatures T between 1550 and 1700 K. At each T, the islands decay at a constant rate, irrespective of their initial position in the mounds, indicating that mass is not conserved locally. From temperature-dependent island decay rates, we obtain an activation energy of 2.8+/-0.3 eV. This is consistent with the detachment-limited decay of 2D TiN islands on atomically-flat TiN(111) terraces [Phys. Rev. Lett. 89 (2002) 176102], but significantly smaller than the value, 4.5+/-0.2 eV, obtained for bulk-diffusion-limited spiral step growth [Nature 429, 49 (2004)]. We model the process based upon step flow, while accounting for step-step interactions, step permeability, and bulk mass transport. The results show that TiN(111) steps are highly permeable and exhibit strong repulsive temperature-dependent step-step interactions that vary between 0.003 and 0.076 eV-nm. The rate-limiting process controlling TiN(111) mound decay is surface, rather than bulk, diffusion in the detachment-limited regime.

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S. Kodambaka, Navot Israeli, J. Bareno, W. Swiech, Kenji Ohmori, I. Petrov, J. E. Greene. 2004-05-08. Low-Energy Electron Microscopy Studies of Interlayer Mass Transport Kinetics on TiN(111). https://doi.org/10.1016/j.susc.2004.05.005

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