Growth mechanism for vertical growth of nanopillars in progressive annealed HWCVD grown silicon nanostructures

Here we propose a growth mechanism for the vertically growing conical nanopillars in progressive annealed samples grown using Hot Wire CVD process. Paramagnetic defects are present in a-Si:H films grown at low temperatures (Ts<300°C). During progressive annealing, at around 500°C, dehydrogenation of a-Si takes place; but at higher temperatures rehydrogenation alongwith crystallization of a-Si facilitates the vertical growth of nanopillars.