A novel approach towards silicon nanotechnology

Growth interruption and H-plasma exposure on stacking layers provide an intellectually challenging route for the deposition and control of Si nanostructures. Atomic H of the plasma not only acts as the terminator of the dangling bonds but also plays an important role in the chemical reactions during the propagation of the Si network, by offering either topological freedom or chemical potential to the growing surface. The use of time modulated gas flow in plasma enhanced chemical vapour deposition (PECVD) gives an additional degree of flexibility to the process of nucleation, growth, and control of grain size in the development of Si nanostructures. The density and the size of the nanocrystallites can be controlled by suppressing growth of nucleated Si particles within a critical dimension by optimization and repetition of deposition/plasma-exposure cycles. The degree of H-plasma treatment and the growth temperature both have individual influences on nanocrystallization. Nano-Si structures are obtainable with very narrow thicknesses and at a very low temperature, utilizing standard deposition techniques like PECVD, commonly used in silicon semiconductor technology, and thus hold great promise in device fabrication, extending a novel approach towards silicon nanotechnology.