Possible origin for (110)-oriented growth of grains in hydrogenated microcrystalline silicon films

We have measured the temperature dependence of preferentially oriented growth of hydrogenated microcrystalline silicon films, prepared by reactive hydrogen plasma sputtering of silicon. X-ray-diffraction measurements showed that the relative number of (110) grains increased rapidly at the expense of the (111), but not (311), directions with increasing substrate temperature between 60 and 400 °C. Over the same temperature range grain sizes for all orientations increased in scale with each other. Calculations of the step energy for grains of different sizes and orientations suggest that the changing number of dangling bonds with increasing grain size may be responsible for the observed temperature dependence of the preferential growth.