High-density plane deposition kinetics and facet propagation in silicon-selective epitaxial growth

摘要

This paper reports morphological results and kinetics of the main high-density planes obtained after silicon growth on two different etched figures exhibiting the {3 1 1} and/or {1 1 1} planes. These etched profiles were generated by HCl chemical vapour etching on SiO_2-patterned wafers with the (0 0 1) orientation. Deposition was performed after SiO_2 removal on a full-sheet wafer with a chlorinated chemistry. Scanning electron microscope observations after silicon growth at temperatures between 700℃ and 850℃ permitted us to show that the appearance of the different facets is strongly dependent on the etch profile and on the chamber temperature. Besides that, these results permitted us to point out the difficulty in doing an acceptable silicon epitaxy on the {1 1 1} plane at low temperature (< 750℃). Moreover, we could extract the growth rates of the different high-density planes and we obtained values of activation energies associated with different populations: the values for the {1 0 0} and {1 1 1} planes are different when the {3 1 1} and {9 1 1} planes exhibit very close values.