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arXiv · 1711.08401

Reaction paths of alane dissociation on the Si(001) surface

Richard Smith·David R. Bowler
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Abstract

Building on our earlier study, we examine the kinetic barriers to decomposition of alane, AlH$_3$, on the Si(001) surface, using the nudged elastic band (NEB) approach within DFT. We find that the initial decomposition to AlH with two H atoms on the surface proceeds without a significant barrier. There are several pathways available to lose the final hydrogen, though these present barriers of up to 1 eV. Incorporation is more challenging, with the initial structures less stable in several cases than the starting structures, just as was found for phosphorus. We identify a stable route for Al incorporation following selective surface hydrogen desorption (e.g. by STM tip). The overall process parallels PH$_3$, and indicates that atomically precise acceptor doping should be possible.

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Richard Smith, David R. Bowler. 2017-11-22. Reaction paths of alane dissociation on the Si(001) surface. https://doi.org/10.1088/1361-648x%2Faaaa91

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